As standard Particle Swarm Optimization (PSO) algorithm has some shortcomings, such as getting trapped in the local minima, converging slowly and low precision in the late of evolution, a new improved PSO algorithm based on Gaussian disturbance (GDPSO) was proposed. Gaussian disturbance was put into in the personal best positions, which could prevent falling into local minima and improve the convergence speed and accuracy. While keeping the same number of function evaluations, the experiments were conducted on eight well-known benchmark functions with dimension of 30. The experimental results show that the GDPSO algorithm outperforms some recently proposed PSO algorithms in terms of convergence speed and solution accuracy.