Telomere length (TL) at birth is related to future diseases and long-term health. Bisphenols exhibit toxic effects and can cross the placenta barrier. However, the effect of prenatal exposure to bisphenols on newborn TL remains unknown. We aimed to explore the effects of prenatal exposure to bisphenols (i.e., bisphenol A (BPA), bisphenol B (BPB), bisphenol F (BPF), bisphenol S (BPS), and tetrabromobisphenol A (TBBPA)) on relative TL in newborns. A total of 801 mother–infant pairs were extracted from the Guangxi Zhuang Birth Cohort (GZBC). The relationships between bisphenol levels in maternal serum and relative TL in cord blood were examined by generalized linear models and restricted cubic spline (RCS) models. After adjusting for confounders, we observed a 3.19% (95% CI: -6.08%, -0.21%) reduction in relative cord blood TL among mothers ≥ 28 years with each 1-fold increase of BPS. However, each 1-fold increase of TBBPA, a 3.31% (95% CI: 0.67%, 6.01%) increased in relative cord blood TL among mothers < 28 years. The adjusted RCS models also revealed similar results (P overall < 0.05, P non-linear > 0.05). This is the first study to show a positive association between serum TBBPA levels and newborn relative TL among younger mothers. However, BPS levels were inversely correlated with TL in fetus born to older mothers. The results suggest fetuses of older pregnant women are more sensitivity to BPS exposure and accelerated aging or BPS-related diseases in later life may stem from early-life exposure.