The invention discloses a method and device for realizing calculation of sine and cosine functions. The method comprises the following steps of: 1) judging whether an input angle is in an appointed range or not, if the judging result is positive, outputting the input angle as a target calculation angle, and otherwise, compressing the input angle and outputting the compressed angle as the target calculation angle; and 2) carrying out sine or cosine function calculation on the target calculation angle by adoption of a TCORDIC algorithm, when the difference between the target calculation angle and a degree of 0 or Pi/2 is smaller than an appointed threshold value, completing the sine or cosine function calculation through a Taylor expanded form, and otherwise, completing the sine or cosine function calculation by using a CORDIC algorithm. The device comprises an angle compression unit and a TCORDIC calculation unit. According to the method and device, the calculation of sine and cosine functions of any angle can be realized; and the method and device have the advantages of being simple in realization method, low in calculation complexity and high in calculation efficiency and precision.