Due to rule enforces state liability for that lawful act is difference with the liability from unlawful act included liability on contract not for general contract or state sector contract has different from tort liability so it is necessary to study another article. This research has objectives to study the state liability only in case tort liability of state in Thailand whether it has suitable or relate to current situation or not. The problems and unsuitable are specified the rule of liability by taking guidance of comparison with international law exclude the liability on contracts or in any cases. For it is guidance to analyze study to liability of state in Tortious Liability of Officials Act B.E. 2539 is necessary to study why the state or official state must be liable for violation of administration and why the state or state officials is liable for violation of staff in performance of duties because the liability of state is when state can be duty right holder and liability by enterprise. In preliminary shall say about the definition of type and status of enterprise then say about law is able enforced and the court has authorization still included liability of state and state officials.