Abstract: Aim To study the VLSI oriented algorithm of trigonometric function and its correspondent circuit architecture. Methods The CORDIC algorithm was used firstly to deduce the algorithm of evaluating trigonometric function. In order to get the effective algorithm of evaluating trigonometric function, the trigonometric function of multiple angles was used. Results and Conclusion The multiple angle algorithm that has a simple circuit architecture and can be used to evaluate the trigonometric function of any angle without looking up the value table of trigonometric function was gotten. The improved CORDIC algorithm and its correspondent VLSI array architecture were acquired at the same time. The correctness of two kinds of algorithm was proved by computer simulation results.