Non-edible jatropha oil was catalyzed by the sulfurated NiMo/activated clay catalyst to produce the second generation biodiesel. By the method of isovolumetric impregnation plus in-situ activation by CS2，a sulfurated NiMo/activated clay catalyst was prepared, and the structure and performance of the catalyst were studied by XRD, BET, Py-FTIR and NH3-TPD techniques. The effects of different reaction conditions such as reaction temperature, catalyst dosage, hydrogen pressure, reaction time on the reaction were investigated. The experimental results show that the optimal reaction conditions are as follows: the reaction temperature is 300 ℃，the catalyst mass fraction is 7.5%， the initial hydrogen pressure of the reaction is 3.5 MPa, and the reaction time is 60 min. Under these conditions，the conversion ratio of jatropha oil and the selectivity to C15-C18 reached 84.53% and 95.19%，respectively. The main components of optimal product were analyzed. With the sulfurated NiMo/activated clay, the second generation biodiesel with the main components of C15-C18 alkenes was obtained via the reactions of hydrogenation saturation, hydrodeoxygenation, hydrodecarbonylation and cracking.