In this research, the SAPO-34 nanocatalyst has been improved in order to produce biodiesel as a green fuel. According to large molecules of free fatty acids (FFAs) and difficulty in the diffusion of these molecules through small pores of SAPO-34, the active charcoal secondary template was used to create meso and macro pores. Also, in order to increase acidic strength and density of active sites, CeO2 particles were accommodated to the structure of mesopores SAPO-34 by sono-solvothermal treatment and using ultrasound irradiation powers of 0, 100, 200 and 300 W. The synthesized catalysts were evaluated by FESEM, FTIR, TPD-NH3, HRTEM, XRD, and BET-BJH analyses. Results of characterization and reactor tests indicate that increasing the ultrasound irradiation power from 0 to 300 W in the synthesis stage has a significant effect on improving nanocatalysts properties and their performance in producing biodiesel, such that the conversion percentage in esterification reaction increased from 77 to 94%. The BET analysis showed, firstly, that using active charcoal leads to an increase of mean pore diameter of SAPO-34 from 0.5 to 3.4 nm, and secondly, that by using ultrasound irradiation power of up to 300 W, the pore volume in meso and macro range increases by 2.5 times. Results of the reactor test for the Ce/MSAPO-34 catalyst revealed that increasing the temperature, reaction time, and mole ratio of methanol to oil leads to an increase in conversion of oleic acid to biodiesel. Studying the kinetics of esterification reaction showed that using ultrasound irradiation powers of 100, 200, and 300 W increased the reaction rate by 20%, 30%, and 40%, respectively.