According to the legal vacuum in retroactive and no retroactive effects of nullity in the labor contract, this article examines the views on this topic and identifies the effects of each in a descriptive, analytical and comparative approach. The result was that one could deduce the legislative to nullity the contract in accordance with the general contract rules. In French, German, Italian, and Luxembourg law, the no retroactive effect of nullity has been accepted because of pay and its fringe benefit to the worker. In this article, the same result has been achieved in our rights to the rules of "liability of usurper" and "Ma Yozman". But in cases where nullity is with bad faith (such as the nullity caused by the wrongdoing of the employer in the personality of the worker and an illicit contract), because of prohibiting the use of bad faith people with legal protections and contrary to public policy, a labor contract cannot create such benefits for them. Regarding labor imperative regulations as mentioned in the laws of foreign countries and in our labor law, some of those cases have been criminalized. In any case, even with the cancellation of the contract, their compliance is mandatory.