The influences of principle quantum number and laser power on dipole blockade effect are analyzed by calculating dipole blockade effect of Rydberg state rubidium atoms with kinetic Monte Carlo method. The dipole blockade effect is enhanced with increasing of the principle quantum number and laser power. When the laser power is high enough, atoms excited to Rydberg state tend to be saturated. Results show that the dipole blockade effect of Rydberg atoms can be controlled by selecting Rydberg states of rubidium atomic energy level and adjusting laser power, which has important applications in producing quantum bits and quantum information processing.