Provided are a switch transmission mechanism and a power switch. The switch transmission mechanism comprises a push rod for connecting to a first contact member, a connection rod for connecting to a second arcing contact, a driving-side mechanism and a driven-side mechanism. A fixed plate is provided thereon with a first fixed plate guide groove for the push rod to slide therein, a second fixed plate guide groove for the connection rod to slide therein and a fixed plate sliding groove. One end of the fixed plate sliding groove is adjacent to the first fixed plate guide groove, and the other end thereof extends to the direction of the second fixed plate guide groove and exceeds the second fixed plate guide groove by a part. The driving-side mechanism comprises a driving rod, a driving pin and a driving arm; the driving arm is provided thereon with a driving arm sliding groove and can rotate about a fixed shaft fixed on the fixed plate; one end of the driving rod is hinged with the push rod via a rotary hinge, and the other end thereof fixes the driving pin; and the driving pin can slide along the driving arm sliding groove and the fixed plate sliding groove. The switch transmission mechanism of the present invention has small space occupation, and the motion curve of an arcing contact can satisfy the requirements of electric current ON/OFF well.