The utility model discloses a microscope zooms mechanism, including a fixed cylinder section of thick bamboo, a rotating cylinder section of thick bamboo, shell, compensation group and change times group, set up the twice cam groove on the rotating cylinder section of thick bamboo lateral wall, set up the axial long slot bore on the fixed cylinder section of thick bamboo lateral wall, compensation group doubly organizes slidable mounting in fixed cylinder section of thick bamboo inboard with becoming, compensation combination becomes doubly to organize radially installs first roller and second roller on the lateral wall respectively, fixed cylinder barrel casing dress in a rotating cylinder section of thick bamboo, first roller and second roller pass behind the long slot bore of fixing on the cylinder section of thick bamboo lateral wall respectively with rotating cylinder section of thick bamboo lateral wall on cam groove sliding fit, the rotating cylinder barrel casing is cased, and through the 2nd countersunk screw fixed connection, the structure that can solve current microscope zooms mechanism is complicated, and the guidance quality can the poor problem poor with cooperating the precision.