The employment prohibition means that some person can be only employed in some kind of works or only if some kinds of conditions are applied; and the prohibition of employment in another work means that the worker cannot change its work and he cannot take additional works. In this way it will be created compliance between the physical capacity of the worker and the work conditions. This situation makes the prohibitions a fundamental concept of the work health and safety. This is a subject of limitation of the freedom of work contact concluding or changing the scope of the contract of the employer through public order and rules of law. The employment prohibition consists of absolute prohibition and conditional prohibition. The absolute prohibitions depend on the gender, age, work period, characteristics of worker, employer and representative of the employer and whether the work contract is in suspense or expired. Some kinds of conditional prohibitions are grouped in health report, profession and permission of the worker. The prohibition of another works is related with tasks of the worker, features of the work and suspense of the work contract in some situations. The noncompliance with prohibitions makes the employment contract annul; the employer will be faced against some legal and penal clause sanctions.