The scheme of silicon-based integrated optical gyroscope is proposed firstly,and the curve radius and transmission loss of the curve waveguide are calculated theoretically.The essential parameters which are the width and length,are simulated with the relationship with transmission loss,and the "K" shape coupler is designed by the R-soft simulation based on the theoretical analysis result.The experimental setup is constructed,and the loss and the optical mode are tested,respectively.The loss measurement results show that the loss is 0.014 dB/cm,which validates the theoretical calculation result that the transmission can be neglected when the ratio of l2/h is greater than 5 000.Finally,the optical mode is tested by beam-scan,which shows the perfect fitting result with the ideal Gauss mode curve.