The utility model discloses a convenient to use's film thickness measuring device, comprising a base plate, the last fixed surface of bottom plate is connected with the riser, the positive fixedly connected with slide rail of riser, sliding connection has the slider in the slide rail, the positive fixedly connected with tooth dental lamina of slider, one side interlude of just keeping away from the slide rail on the riser has the bull stick, cup jointed the gear on the bull stick, and tooth dental lamina and gear engagement, the one end of bull stick just is located the rear fixedly connected with crank of riser, the bottom fixedly connected with slide caliper of tooth dental lamina. The utility model discloses a to slide caliper's improvement, can change slide caliper's height through the tooth dental lamina, convenient adjustment is to the measuring position of film, because the one end of film is worn out between by two rollers to gap between two rollers is located same water flat line with the cloth roller, can and the surface the fold can not appear, reach the film fully expand labour saving and time saving and measure accurate effect.