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It has been reported that the proliferation and apoptosis of mammary epithelial cells affect milk production. Therefore, ensuring adequate mammary epithelial cells is expected to enhance milk production. This study is devoted to studying the effects of kisspeptin-10 (Kp-10), a peptide hormone composed of 10 amino acids, on bovine mammary epithelial cell (bMEC) proliferation and exploring the underlying mechanism of its action. bMECs were treated with various concentrations of Kp-10 (1, 10, 100, and 1,000 nM), and 100 nM Kp-10 promoted the proliferation of the bMECs. Kp-10 promoted the cell cycle transition from G1 to the S and G2 phases, increased the protein levels of Cyclin D1 and Cyclin D3, and reduced the expression levels of the p21 gene. This study also showed that inhibition of G protein-coupled receptor 54 (GPR54), AKT, mTOR, and ERK1/2 reduced the proliferation of the bMECs that had been induced by Kp-10. In addition, Kp-10 decreased the complexes formed by Rb and E2F1 and increased the expression levels of the E2F1 target genes. These results indicate that Kp-10 promotes bMEC proliferation by activating GPR54 and its downstream signaling pathways. K E Y W O R D S4EBP1, bMEC, Kp-10, proliferation, Rb/E2F1

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High‐producing dairy cows are prone to oxidative stress due to their high secretion and strong metabolism, and excessive oxidative stress may cause the apoptosis of bovine mammary epithelial cells (bMECs). Myricetin (Myr) has been shown to have a wide range of pharmaceutical activities. The aim of this study was to evaluate the effect of Myr on hydrogen peroxide (H2O2)‐induced oxidative stress and apoptosis in bMECs and to clarify the underlying mechanism. bMECs were pretreated with or without Myr and then stimulated with H2O2. The results showed that Myr significantly increased the total antioxidant capacity and superoxide dismutase levels and decreased the malondialdehyde (MDA) and reactive oxygen species (ROS) levels in a model of oxidative stress induced by H2O2 in bMECs. Mechanistic studies found that Myr inhibited H2O2‐induced oxidative stress in bMECs through the adenosine monophosphate‐activated protein kinase/nuclear factor erythroid‐2 related factor 2 (AMPK/NRF2) signaling pathway. Additional research found that Myr could also inhibit H2O2‐induced apoptosis in bMECs through NRF2. These data suggest that Myr effectively alleviated oxidative stress and apoptosis in H2O2‐induced bMECs through the activation of the AMPK/NRF2 signaling pathway.