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Molybdenum has high melting point, low thermal expansion coefficient and excellent stability. It has broad application prospects in plasma propulsion and electric vacuum devices so that its secondary electron emission characteristics have gradually attracted the attention of researchers. Firstly, the secondary electron yield (SEY) and secondary electron spectrum (SES) of molybdenum were studied experimentally. Then the test data were analyzed by the relevant model. Finally, the SEY model of molybdenum is established by Monte Carlo method to analyze the influence of work function on SEY. The results show that the maximum value of SEY is 1.77, which is significantly lower than that of silver-plated aluminum alloy. When the incident electron energy changes, the most probable energy of the true secondary electron peak of the SES is basically unchanged, while the position and intensity of the elastic backscattered electron peak change accordingly. Among all kinds of secondary electrons, true secondary electrons are most affected by the work function.