An improved and rapid three dimensional Gerchberg-Saxton (GS) algorithm based on the classic GS algorithm for computer generated holograms is proposed and applied to holographic optical tweezers. Theoretical simulations and experimental results have demonstrated the rapidity and efficiency of the proposed algorithm. A robust holographic optical tweezers setup based on phase-only liquid-crystal spatial light modulator(SLM) is built, and stable trapping and dynamic manipulation of yeast cells and silica beads with large array traps in three dimensions are demonstrated. Two special traps, i.e., line trap with intensity gradient distribution and optical vortex trap, are generated to transport and rotate micro-particles respectively. The system is verified to be robust on particles manipulations, which provides a new and powerful tool for researches on biology, colloid physics and so on.