The production organized in flexible manufacturing cells (FMC) can be a complicated issue when they are constrained by machines, robots, equipment and some other resources. Since machines and robots are the main bottleneck to the efficiency of FMC, this paper focused on the modeling and scheduling problem constrained by machines and robots. A common model representation, colored timed Petri net (CTPN) was utilized to build a FMC model constrained by robots and machines, which was then transformed to the simulation model. The scheduling problem was studied to establish a mathematical model of the FMC constrained by machines and robots. According to the model, a genetic algorithm was proposed to search an optimal solution by using an indirect coding of scheme. The effectiveness of the proposed algorithm was validated via an instance and the comparison with the result from the solution of simulated annealing algorithm.