Background: To systematically review the association of circulating kisspeptin and spontaneous abortion. Methods: Four English and two Chinese databases were used to identify relevant studies. Two reviewers independently screened the search results, extracted data, and assessed the quality of the literature. A random effects model meta-analysis of the standardized mean difference was conducted, and the I{}^{\mathrm{2}} index was used to assess heterogeneity. Results: Nine observational articles were included, comprising 312 patients with spontaneous abortion and 1395 controls (intrauterine pregnancy). The meta-analysis showed that the spontaneous abortion group had significantly decreased circulating kisspeptin levels [standardized mean difference = –2.78 (–4.48, –1.09), p = 0.001] compared with the intrauterine pregnancy group. Inconsistent adjustment for confounders and significant between-study heterogeneity were noted in this study. Conclusions: Circulating kisspeptin levels were lower in the spontaneous abortion group than in the intrauterine pregnancy group, which indicates that kisspeptin might be an independent biomarker of spontaneous abortion. Due to the limited quality and quantity of the studies included, more high-quality studies are required to verify the above conclusion.