Because of the large long-term drift, the commercial semiconductor laser cannot meet the requirement of the experiments of laser cooling and probing of single ions trapped in ion traps of optical frequency standards for a long time. So, the transfer cavity is used to reduce the long-term drift of a commercial 397 nm laser. An ultra-narrow 729 nm laser stabilized to a super cavity by Pound-Drever-Hall (PDH) scheme is used as reference, and a scanning Fabry-Perot (F-P) cavity is used as transfer medium. The 397 nm laser′s long-term drift is reduced to less than 1 MHz within 1 h, and the square root of the Allan variance is 1×10-10 at an averaging time of 102 s. These parameters are the base for stabilizing an 866 nm laser and optimizing the laser cooling and long-term measurement of single 40Ca+ ion.