Abstract: A new low-loss wide-angle Y branches is proposed based on the graded-index waveguides in this paper. The Results of theoretical analysis and the simulations by finite-difference beam propagation method (FDBPM) show that the radiation losses can be less than 0.18 dB even if a branching angle is as large as 10°. Compared with traditional Y branches, the new Y branches is characteristic with low losses and simple structure.