Abstract: Objective To study the serum C1 q/tumor necrosis factor-related protein 6(CTRP6) level in pregnant women with gestational diabetes mellitus(GDM) and its relationship with insulin resistance and inflammatory cytokine levels, and to explore the role of CTRP6 in GDM. Methods A total of 86 patients with GDM who were hospitalized and delivered in Quzhou Maternal and Child Health Hospital from January 2019 to December 2019 were selected as group B, and 86 normal pregnant women who were hospitalized and delivered during the same period were selected as group A. The fasting blood glucose(FPG), glycated hemoglobin(HbA1 C), fasting insulin(FINS) and high-sensitivity-C reactive protein(hs-CRP) levels were measured. The islet-β cell function index(HOMA-β) and insulin resistance index(HOMA-IR) were calculated. The levels of serum CTRP6, interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α) were measured by enzyme-linked immunosorbent assay(ELISA). Results The serum CTRP6, FPG and HbA1 C levels in group B were higher than those in group A(all P<0.05). FINS and HOMA-IR in group B were higher than those in group A(all P<0.05), and HOMA-β was lower than that of group A(P<0.05). The levels of serum hs-CRP and TNF-α in group B were higher than those in group A(all P<0.05). The serum CTRP6 level was positively correlated with FPG, HbA1 C, FINS, HOMA-IR, hs-CRP, IL-6 and TNF-α levels(all P<0.05), and was negatively correlated with HOMA-β(P<0.05). Conclusion The serum CTRP6 level in GDM patients is elevated, and its level is closely related to insulin resistance and serum inflammatory cytokine levels.