Background: This study introduced the Perinatal Grief Intensity Scale (PGIS) and applied it to assess the reliability and validity of perinatal loss in Chinese mothers. Methods: To sinicize PGIS and cultural debugging of the scale, reliability validity was assessed in this prospective cross-sectional study. Results: The Chinese version of the PGIS contained 14 items in three dimensions: reality, confront others, and congruence. The content validity index (CVI) at the total scale level, mean scale level, and item level was 0.92, 0.909, and 0.860–1.000. Exploratory factors were identified as three metric factors with a cumulative variance contribution rate of 66.627%. The Chinese version of the Perinatal Grief Scale (PGS) was used as a calibration standard, and the correlation coefficient was 0.759. The total Cronbach’s alpha coefficient for the Chinese version of the PGIS was 0.768, with a fold-half reliability of 0.749. The scale showed good reliability and validity. Conclusions: The Chinese version of the PGIS was used as a calibration standard by exploratory factor testing, and the correlation coefficient was good, and the scale had good reliability and validity for application in China.