Case analysis and trends

Korea treats drug offences far more strictly than many countries its foreign residents come from. Something that is legal, tolerated or even prescribed at home can lead to a criminal case here. For a foreign national, a drug case also puts residence in Korea at risk. This article explains how the law is applied, how cases usually begin, and why early decisions matter.

What the law covers

The Narcotics Control Act (마약류 관리에 관한 법률) covers three groups of substances: narcotics such as cocaine and heroin, psychotropic substances such as methamphetamine, MDMA and some prescription medicines, and cannabis (대마). Using, possessing, buying, selling, receiving and importing them are all separate offences.

The fact that cannabis is legal in the country where you bought it, or where you come from, does not help. Using or possessing it in Korea is a crime under Korean law.

How drug cases usually start

People are often surprised by how the investigation reached them. Common starting points are:

Medicines are a particular risk

Some medicines that are prescribed abroad, for example certain ADHD treatments, strong painkillers and sleeping pills, contain controlled substances in Korea. Bringing them into the country, or having them sent by post, without following the rules can be treated as illegal import.

If you need such a medicine, check before you travel whether it is controlled in Korea and whether advance approval from the Ministry of Food and Drug Safety (식품의약품안전처) is required. Carry the prescription and bring only the quantity for your personal use.

Why the stakes are higher for foreign nationals

A drug conviction affects a foreign national in two ways: the criminal penalty and the immigration consequence. Under Article 46 of the Immigration Act, a foreign national sentenced to imprisonment or heavier, including a suspended sentence, can be deported. Deportation is usually followed by a ban on re-entering Korea for a period of years. Drug offences are also treated as a serious negative factor in any future visa, permanent residence or naturalization application.

During the investigation, you may be banned from leaving Korea (출국정지). Detention is also more likely in drug cases, particularly where investigators believe evidence might be destroyed or the person might leave the country.

What makes a difference

Outcomes in drug cases vary widely with the substance, the amount, whether it was for personal use or sale, and whether it is a first offence. Some factors are within your control:

Things that tend to matter
· Do not delete messages, throw away items or contact others involved. Destroying evidence can itself lead to detention and a harsher outcome
· Get legal advice before the first interview. Statements made early are difficult to take back
· Be careful with consent to phone searches and tests. Understand what you are agreeing to
· For personal use cases, voluntary treatment and counselling can be relevant. Prosecutors can suspend an indictment on the condition of treatment (치료조건부 기소유예)
· Evidence of a stable life in Korea, such as work, study and family, can matter both to detention and to the outcome

Speak with a lawyer about your situation

Call 1533-7377 or request a consultation at daehanlaw.com/en/reservation.

After you apply, a consultation manager calls you back and explains the consultation fee. Consultations can be held in English, Chinese, Japanese, Russian, Vietnamese or Uzbek, or with an interpreter.

Laws referred to

Narcotics Control Act (마약류 관리에 관한 법률); Immigration Act (출입국관리법) Articles 11, 29 and 46

Frequently asked questions

I only used cannabis once, at a party. Is that really a crime?

Yes. Using cannabis in Korea is a criminal offence, even once. A first offence for personal use is treated differently from supply or import, but it is still a case that can lead to a criminal record and affect your visa.

I ordered CBD oil online. Is that a problem?

It can be. Many products sold as CBD contain cannabis ingredients that are controlled in Korea. If a parcel is stopped at customs, the case can be treated as import rather than simple possession. Get advice before answering questions about it.

Will I definitely be deported?

Not in every case. Deportation depends on the sentence and on immigration's own decision, which considers your circumstances. Outcomes such as a suspension of indictment carry a much lower risk than a sentence of imprisonment. That is why the handling of the criminal case matters for your stay.

Daehanjoongang Law Firm | Haeundae Office

Managing Attorney Han Byung-chul

7F Raon J Building, 554 Haeundae-ro, Haeundae-gu, Busan 48093

Phone: 1533-7377 | Email: hanbyungchul@naver.com

This article is general information about Korean law, not legal advice. The outcome of any matter depends on its own facts. Consultations are paid.

This article was drafted with the help of AI tools. Last updated 2026-09-23.