The object of this study is to conduct research on a fluidized catalytic cracking unit with a riser reactor. A dynamic mathematical model comprising startup, shutdown and routine operation has been developed, and the results of the simulation calculations have been analyzed. The model will enable engineering and technical personnel to carry out research on the operation, performance, process optimization and the development of a control system for a catalytic cracking unit. This model can also be used on a simulator for training operating personnel.