A novel method to design Y-branch waveguides is proposed by using total internal reflection, and the optical properties areanalyzed. The simulated results show that the optical loss values of two Y-branch waveguides with the branching angles of12o and 30o are only 0.310 dB and 0.645 dB, respectively. Compared with conventional Y-branch waveguides, the opticalperformance of the proposed ones is well improved, which has many advantages such as wide angle, low loss, simplestructure and easy for fabrication. A novel method to design Y-branch waveguides is proposed by using total internal reflection, and the optical properties areanalyzed. The simulated results show that the optical loss values ​​of two Y-branch waveguides with the branching angles of 12o and 30o are only 0.310 dB and 0.645 dB, respectively. Compared with conventional Y-branch waveguides, the optical performance of the proposed ones is well improved, which has many advantages such as wide angle, low loss, simplestructure and easy for fabrication.