The invention provides a cotton delinter for pesticide residue tests. The cotton delinter comprises a frame, a motor, a seed stirring working box, a saw blade drum and a hair brush drum. The seed stirring working box, the saw blade drum and the hair brush drum are connected from top to bottom successively and are internally communicated with one another. The output shaft of the motor is connected with a motor belt wheel. One end of a seed stirring roller in the seed stirring working box is connected with a seed stirring roller belt wheel. The lower end of the seed stirring working box is opened and is connected with a cotton seed collecting box. A rotating shaft is arranged in the saw blade drum and is provided with a plurality of saw blades. One end of the rotating shaft in the saw blade drum is connected with a saw drum belt wheel. A drum brush is arranged in the hair brush drum. One end of a rotating shaft in the hair brush drum is connected with a hair brush belt wheel and the other end is connected with a guide wheel. The seed stirring roller belt wheel and the guide wheel are connected with each other by a first triangular belt. The hair brush drum is provided with an air outlet. A tensioning wheel is arranged at the lower portion of the frame. The motor belt wheel, the saw drum belt wheel, the hair brush belt wheel and the tensioning wheel are connected through a second triangular belt. The cotton delinter is high in short cotton velvet peeling efficiency, is easy to operate, is high in operation safety, is simple in structure and low in manufacture cost and is highly practical.