Do language schools ask for a criminal record check?

It is not standard for D-4 language programs. Start it only if the specific school you are applying to asks for it.

Where it does come up:

1. A small number of schools request it as their own admission requirement, usually ones with dormitory placement for younger students or with a strict internal policy. If one school asks and the others do not, that is the school's rule, not a national one.

2. Some consulates request it for particular nationalities as part of risk screening. This varies by country and is not published. Your local Korean consulate's own page is the only reliable source — not a general guide.

3. It becomes standard later if you move to a work visa, especially E-2 teaching visas, where a criminal record check with apostille is mandatory. If a degree or teaching is in your longer plan, you will need one eventually.

What to do now: check the document checklist for each school you are applying to, and check your own consulate's D-4 page. If neither mentions it, do not spend the three weeks.

That said — if it takes three weeks in your country and it is cheap, there is an argument for getting one anyway. It is valid for a period (usually three to six months for these purposes), it removes a possible surprise, and if you later apply for anything else in Korea you already have it. Several students have been asked for one at short notice and lost a fortnight to it.

If you do get it, get it apostilled at the same time. An unapostilled certificate is not accepted for anything official in Korea, and going back for the apostille later means starting the queue again.