In 1885 the Cabinet system was established to replace the traditional Dajokan (Grand Council of State) system, and as a result the Cabinet Legislation Bureau was established inside the Cabinet. It is an administrative agency with a Director-General appointed by the Cabinet at its head.

Since its establishment, the Bureau has belonged to the Cabinet, and has engaged in the examination of draft laws, draft Cabinet orders and draft treaties to be submitted to the Cabinet, as well as interpretation thereof. Through examining to ensure that measures implemented by the Cabinet do not contain any legislative errors, the Bureau plays a supportive role to maintain Japan as a nation ruled by law.