Abstract In this work, we update the catalog of M-giant stars from low-resolution spectra Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) Data Release 9. There are 58,076 M giants identified classification pipeline with seven temperature subtypes M0 to M6. The 2471 misclassified non–M-giant white dwarf binaries, early types, and dwarfs. And contamination rate is 4.2% in M-gia...