The invention discloses an exhaust port of a composite gear tooth compressor. The exhaust port (401) is formed in an exhaust end cover (4); the contour curve of the exhaust port (401) comprises: a left edge curve EF, a right edge curve GH, an upper edge curve EH, a lower edge curve FG, a left upper vertex E, a left lower vertex F, a right upper vertex H and a right lower vertex G; the left edge curve EF, the right edge curve GH and the upper edge curve EH are three circular arcs; and the lower edge curve FG is a partial curve of a first cycloid AB of a first tooth groove (101). The exhaust port (401) is large in area, low in exhaust velocity and small in exhaust pressure loss; power consumption of the compressor and leakage of high-pressure gas at the exhaust port at the end face of a rotor are effectively reduced; and clearance volume formed after the exhaust is finished is small, volume efficiency is high, and meanwhile the internal volume ratio of the compressor is larger.