A cutting structure for plastic film includes a bracket, a first roller, a second roller, a tachometer, a processor, a monitor and a cutter. The bracket includes a bottom and two sidewalls extending from the bottom along a same direction. The first roller includes a shaft fixed to the sidewalls and a sleeve rotatably sleeving on the shaft. The second roller is pivotally connected to the sidewalls. The tachometer is disposed on one end of the second roller and configured for measuring the rotation speed of the second roller. The processor is configured for reading the rotation speed and further calculating a rotation distance of the second roller. The monitor is configured for displaying the rotation distance. The cutter extends upward from the bottom for cutting the plastic film pulled from the first roller and the second roller.