The invention discloses a hormone receptor-positive breast cancer recurrence monitoring gene mutation library construction method, which is characterized that the library covers the total 1357 somatic cell mutations on human genes such as KRAS, JAK3, AKT1, CREBBP, PTEN, RB1, TP53, CTNNB1, TSC2, TSC1, ERBB2, PIK3CA, SF3B1, JAK2, CDH1, SMAD4, GATA3, MAP2K4, MAP3K1 and ESR1. According to the present invention, a plurality of the target sequences are subjected to single tube amplification with the construction method to rapidly complete the library construction, wherein the whole library construction process takes only 2-3 h and the manual time only needs 45 min, such that the difficulty that the multi-gene and multi-target detection of somatic cells on the basis of the small amount of the peripheral blood sample is required in the clinical breast cancer recurrence monitoring is required can be effectively solved, and the lost is low.