Abstract: A method of selecting guide star for star tracker of FY 4 meteorological satellite is proposed. This method is based on the J1991.25 Hipparcos catalog and Pulkovo Compilation of Radial Velocities for Hipparcos Stars, through the rigorous treatment of epoch transformation, the star's position of the FY 4 runtime epoch can be determined. In order to search more accurate guide star, the stars whose magnitudes are brighter than 6.5 of J1991.25 Hipparcos catalog are chosen, and the J2000.0 Hipparcos sub catalog is got after the rigorous epoch transformation. With the help of Tycho 2 star catalog and SAO star catalog at the same epoch, the threshold of position precision is introduced, which can meet the precision of attitude determination in arc second level. The additional guide star (with star flag 5) is brought into use for improving the accuracy and speed of star identification. After the cases analysis of unsuccessful star identification, the guide star which always cause false star identification is given a star flag(such as 6), which denotes that the star is a redundant guide star and can't take part in the star identification processing. Through the introduction of redundant guide star the accuracy of star identification is improved. The 189 additional guide stars distribute all over the whole sky, even the star sparse area. And 34.4% of them are of a magnitude brighter than 3, which can improve star identification. Inaccurate reference guide star causes attitude error inevitably. Comparing with the guide star position of catalog epoch, using the guide star position of FY 4 runtime epoch through rigorous epoch transformation under the limit of the threshold of position precision is a good method to improve the precision of attitude determination.