The utility model discloses a three -dimensional drainage system in connection in series -parallel underground suitable for limit landslide engineering belongs to the drainage engineering field to thesolution has the not good problem of drainage effect that sets up drainage facility, existence on limit (cunning) sloping engineering surface now. It includes collecting system, drainage system, collecting system includes honeycomb duct between sump pit, well, faces upward oblique drain pipe and delivery port, through guide pipe connection between the well between the bottom of adjacent sump pit,and guide pipe connection delivery port between the well, the one end of facing upward oblique drain pipe is linked together with the sump pit, and the other end of facing upward oblique drain pipe is located sloping internal portion, faces upward the wall of a well tilt up setting of oblique drain pipe along the sump pit, drainage system includes sluicing tunnel, seepage flow pipe and outlet. The utility model discloses can prevent and get rid of watershed side surface water infiltration and basement rock crevice water seepage flow to landslide region, the regional moisture content in greatly reduced limit (cunning) slope.