My child wants to get a job. How old must he or she be to work?There is also work that is prohibited for minors under the age of. 18, as well as minors under the age of 16. Prospective minor workers must secure an employment certificate (or work permit) that verifies their ability to be employed. No employer shall be permitted to work a minor under the age of 16 more than 40 hours a week or more than eight hours in any 24-hour period. A minor age 16 or 17 years old: By state law, 16 and 17 year old high school students may not work after 11 p.m. Generally, 14 is the minimum age for employment under Minnesota state law. Minors under 16 cannot work more than 40 hours a week or more than 8 hours per 24 hour period. Agricultural workers are exempt from this rule.