A new method for detecting the nerve growth factors (NGF) is proposed based on the fluorescence quenching effect of carboxyl quantum dots. The research results show that in the pH7.5 buffer solution, the NGF antigen specifically binds to the carboxyl quantum dot-labeled NGF antibody, which can quench the fluorescence of the carboxyl quantum dots. The fluorescence quenching degree and the NGF antigen mass concentration has a good linear relationship in the range of 1-20 ng/mL, and the linear correlation coefficient is 0.9696 with the detection limit of 1 ng/mL. This proposed method has good anti-interference characteristics and has great potential applications in diagnosis and detection.