Particle swarm optimization is a robust optimization technique based on the movement and intelligence of swarm. It uses a number of particles that compose of a swarm moving around in the search area looking for the best solution. Each particle is behaved as a point in a N-dimensional space. Each particle keeps trace of its locations in the solution space which are related with the best solution (fitness) that has obtained by that particle until now. This value is called personal best, pbest. Another best value that is followed up by the PSO is the best value supplied by any particle in all particles associated solution space. This value is called global best, gbest. The Rastrigin function is a non-convex function used as a performance test problem for optimization algorithms in mathematical optimization. It is a classical example of non-linear multimodal function. Rastrigin functions is a class of functions which are used in global optimization because it has the characteristic to have many local minimum values and one global minimum.The purpose of this study is to find minimum values of Rastrigin problem by using particle swarm optimization. The proposed algorithm is adapted the problem and is coded using C#.Net in Microsoft Visual Studio. By running algorithm in different iterations, the best fitness value has been found and saved into memory in the end of each iteration. Hence, it is aimed at producing the best solution to the problem by using the proposed algorithm and finally the results obtained are evaluated.