Article 19 (Breach of Terms and Conditions of Employment), Labor Standards Act, as last amended by Act No. 12325, Jan. 21, 2014
Article 660 (Notice of Rescission for Future of Contract of Employment in which No Period has been Fixed), Civil Act, as last amended by Act No. 14409, Dec. 20, 2016

Unlike an employer, basically an employee can terminate a contract at any time. Especially, an employee can terminate the contract when the terms and conditions of contract are different in reality.

Even though an employee can terminate the contract at any time, the duty of good faith is required and an employer may claim his/her damage against an employee for leaving irresponsibly.

*Labor Standards Act

Article 19 (Breach of Terms and Conditions of Employment)(1) When any of the terms and conditions of employment as expressly set forth pursuant to Article 17 is not observed, the worker concerned shall be entitled to claim damages on the ground of the breach of the terms and conditions of employment and may terminate the labor contract forthwith.

(2) When a worker intends to claim damages in accordance with paragraph (1), he/she may file a claim with the Labor Relations Commission, and, if the labor contract has been terminated, the employer concerned shall provide travel expenses for returning home to the worker who changes his/her residence for the purpose of taking up a new job.

*Civil Act

Article 660 (Notice of Rescission for Future of Contract of Employment in which No Period has been Fixed) (1) If no period for the employment has been fixed by the parties, either party may give notice to the other party of his intention to rescind the contract for the future at any time.

(2) In the case of paragraph (1), the notice of intention to rescind for the future becomes effective after one month has elapsed from the date of receipt by the other party of such notice.

(3) If remuneration has been fixed on a set and regular periodical basis, the rescission of the contract for the future shall be deemed to be effective after one full period has elapsed from the date of completion of the current period during which the other party received the notice of intention to rescind the contract for the future.