In this paper, a preferential optimization problem of antenna placement for a distributed Multi-Input Multi-Output (MIMO) radar is studied. Considering multiple surveillance regions, the radar performances of preferential regions need to be improved and more choices of placement schemes for desired performance need to be provided. Therefore, we use the Particle Swarm Optimiztion (PSO) with reference point to solve the antenna placement problems. By setting reference points, the performance values of preferential surveillance regions will converge to reference points and reach our requirement. Then, we analyse the performance of proposed algorithm. Finally, numerical results are provided to verify the validity of the proposed algorithm.