The emergency enables the president and cabinet to circumvent parliament when drafting new laws and to restrict or suspend independence and rights.
Thousands of individuals have already been arrested or fired since the unsuccessful coup.
More than 600 schools also have been closed and thousands of state workers fired in a crackdown by the president.
The Turkish government is given radically improved powers for at least three months by the state of emergency.
His cabinet and the president will be able to enforce curfews or limitations on freedom of assembly and on publications in addition to having more powers of arrest.