The first time I heard about blood types in any serious way, I wasn’t even ten years old yet. A friend and I were about to share an ice cream, when out of nowhere he asked me my blood type.
The reason was something else. He genuinely believed that people with the same blood type could share food touched by each other’s saliva without any problem. Medically, of course, that’s completely wrong. But to us at that age, it felt like a pretty reasonable rule.
The First Time Someone Asked My Blood Type
That ice cream incident was only the beginning.
Once I passed the age of ten, the nature of the blood type question changed. It was no longer about sharing a cookie someone had bitten into. Now people asked your blood type because they wanted to know your personality, or to gauge whether you’d be a good match for them in a relationship.
Whenever there was friction among friends, someone would inevitably say, “Hey, what’s your blood type?” As if that one piece of information explained the other person’s behavior. Quietly asking a new friend, or someone you had a crush on, for their blood type was a fairly common thing too.
And back then, it was a pretty serious question. Looking back now it makes me laugh, but at the time we truly believed that the essence of a person was contained within four types: A, B, O, and AB.
What Each Korean Blood Type Is Supposed to Mean
So what kind of personality did each blood type get tied to in Korea?
The formula I heard most often growing up went like this. Type A is calm and meticulous. Type B is self-centered, but once they’ve decided in their heart that you’re “their person,” they treat you endlessly well. Type O is outgoing, good-natured, and generous. And type AB, in a word, is impossible to read.
These were stereotypes, not facts. But they were familiar enough that many Koreans understood the joke immediately.
And strangely, there were times when it felt like it fit. I once dated someone with type AB blood, and they really did seem like they were on another wavelength. No matter how closely I looked, I could never quite figure out what was going on inside them. On the other hand, when I dated someone with type A, there was definitely a shy, detail-oriented side to them.
Of course, this isn’t science. Two people who are both type A can be worlds apart, and there’s no evidence anywhere that blood type determines personality. In Korea, the blood type personality idea was used less as a matter of truth and more as a light code for quickly sorting people and opening a conversation.
Did Koreans Actually Believe It?
Here comes the question foreigners are probably most curious about. Did Koreans actually believe this?
Honestly, when I was young, I really did believe it. And the stranger part is that there were plenty of people around me who genuinely acted in line with their blood type image. Type B people being type B, type AB people being type AB. It’s impossible to say which came first. Whether people shaped themselves to fit the blood type image, or simply wanted to see it that way.
People back then tried to explain others through blood type. But the me of today sees it differently. What makes a person isn’t the type they were born with, it’s the time they’ve lived through and the experiences they’ve been through. How someone has lived explains them far more than what they were born as.
Still, one memory stays with me. In the talk about dating compatibility, there was a saying that type A and type O go well together, and I do remember feeling most at ease when I dated someone with type A. But I can’t say that was because of blood type. It’s far more likely that the person themselves was simply that kind of easygoing person.
The “Type B Man” and Other Dating Myths
There was even a time when blood type sat right in the center of Korea’s dating conversation.
The most famous case was the “type B man.” The image of the type B man as a bad boyfriend spread like a trend, and there was even a movie made on the theme. Alongside it came the idea that type B people, whether men or women, tend to be strong-willed when it comes to relationships.
It sounds like a joke now, but I’ll say it again: back then it was fairly serious. When someone said “I’m type B,” the other person really did hesitate for a moment. It was an era when a single blood type could nudge a first impression slightly off course.
This shows that in Korea, the blood type personality idea went beyond mere small talk and once worked as a small filter for dating and first impressions. It was similar to talk of star signs or zodiac animals, yet it had crept a little deeper into everyday life than those did.
Why MBTI Replaced Blood Types
So what about now? The scenery has changed completely.
These days, people don’t ask about blood type as often as they used to. Even among people my age, only the ones who still believe in blood type personalities might occasionally ask. After turning thirty, I’ve been asked my blood type exactly once, and that was recently.
What took its place is MBTI. The casual question you toss at someone you’ve just met in Korea today isn’t “What’s your blood type?” but “What’s your MBTI?” The method, sorting personality into a few letters, using it to open a conversation, weighing dating compatibility with it, stayed exactly the same. Only the tool for sorting switched, from blood type to MBTI.
So the blood type personality idea didn’t so much disappear as hand off its seat across generations. The desire to know someone quickly, the urge to sum up a first impression with a short code, all of that remains. Only the code itself changed with the times.
The Ice Cream, Decades Later
Let me go back to that ice cream.
If someone in Korea suddenly asked you “What’s your blood type?” in 2026, honestly, even I as a Korean would feel a little caught off guard. People don’t ask that the way they used to. So as a foreign traveler, you probably won’t run into the question much at all.
But if you do happen to hear it, it isn’t an attempt to dig into your health information, nor a move to pass some deep judgment on you. If someone asks your blood type in Korea, you do not need to take it too seriously. You can simply answer, “I’m type O,” or laugh and say, “I don’t know.” In most cases, it is just an old-fashioned way to start a light personality conversation. It’s nothing more than the curiosity of that childhood moment, the one wondering whether we could share a saliva-touched ice cream, lingering faintly in a grown-up conversation.
What is Korean blood type personality?
It’s the popular idea that a person’s blood type (A, B, O, or AB) reflects their personality. In Korea it was long used as a light way to sort people and start conversations, not as a scientific theory.
Why do Koreans ask about blood type?
Historically, it was a quick way to guess someone’s personality or dating compatibility. Asking a new acquaintance or a crush their type was once a casual icebreaker, though it’s far less common today.
Do Koreans really believe blood type affects personality?
Some did, especially in the past, and many people seemed to act in line with their type’s image. But it was always closer to a familiar stereotype than a fact, and most people today treat it as a fading bit of fun.
What does each blood type supposedly mean in Korea?
The common images: type A is calm and meticulous, type B is strong-willed but devoted to their inner circle, type O is outgoing and generous, and type AB is hard to read. These are stereotypes, not facts.
Is it rude to ask someone’s blood type in Korea now?
Not rude, just a bit dated. These days MBTI has largely replaced it, so the question feels old-fashioned. If you’re asked, you can answer lightly or laugh it off; it’s just a casual personality chat.
