We study warranty cost analysis for a multi-component product protected by the lemon laws. The product is repairable and consists of critical and non-critical components. The failed product under warranty due to failure of any critical or non-critical component is minimally repaired. It is considered that the product turns to be a lemon when either the number of critical or noncritical component failures reaches k. We obtain the expected warranty cost and the optimal period of lemon laws which are of interest to the manufacturer when the product is protected by the lemon laws, and provide numerical examples to illustrate the expected warranty cost and the optimal lemon law period.