The warp of InP wafers is due to the growth condition of the crystal and the mechanical damage of the wafers.The mechanical damage can be reduced by chemical method.The effect of the etching process parameters,such as the solution proportion,temperature and etching removal,is researched.The results indicate that the warp of InP wafers change with the etching rate,which is effected by the solution proportion and temperature.The higher the etching rate is,the lower the warp of InP wafers is.However,the warp of InP wafers reduce with the etching removal only at certain range.The warp of InP wafers is reduced remarkably when the etching solution is proportion C,the solution temperature is at50℃ and the etching removal is about 5 μm.