Abstract: An anti-tilting transmission mechanism for doors and windows includes a first fixed plate, a second fixed plate, a transmission gear located between the first fixed plate and the second fixed plate, and a transmission rack, wherein: two guide though-holes are respectively provided on two ends of the second fixed plate; two threaded columns, which are capable of moving back and forth, are respectively located within the guide though-holes; two limit ribs are respectively located at an outer edge of a rear end of the threaded columns; two compression springs are respectively located between the first fixed plate and the threaded columns; each of the threaded columns has a threaded hole axially provided thereon, so that after passing through a door and window profile, screws are respectively tightened with the threaded holes on the threaded columns, so as to fix the transmission mechanism onto the door and window profile.