The aim was to evaluate oocyte and embryo production (EP) in lactating dairy cows of low and high body condition score (BCS) presenting different plasma insulin-to-glucose ratio (I:G). Follicles of 290 non-pregnant lactating dairy cows between 80 to 280 d in milk (DIM) were aspirated in random days of the estrus cycle for EP. At the time of follicle aspiration, cows were scored for body condition, and blood was collected for determination of plasma concentrations of glucose and insulin. Data were analyzed as a 2 × 4 factorial design, having BCS and I:G ratio as main factors. Animals were classified as low (≤3.25; LS) or high (>3.25; HS) BCS, and for I:G using its quartile distribution (low – LL, low intermediate – LI, high intermediate – HI, and high quartiles - HH). Insulin-to-glucose ratio increased as I:G quartile distribution increased (0.02, 0.08, 0.15, 0.37 ± 0.01 for LL, LI, HI, and HH, respectively; P < 0.001), but no differences were observed for BCS or BCS × I:G. Similarly, insulin followed previous patterns. On the other hand, glucose was higher (P < 0.05) in HS compared with LS or in LL compared with LI, HI, HH. For BCS main effect, milk yield, DIM, and oocyte and EP were higher in HS compared with LS cows; embryo produced per oocyte collected did not differ between BCS groups. For I:G quartile main effect, EP and embryo produced per oocyte collected were the highest for HI. There were no significant effects of BCS × I:G quartiles for milk yield, oocyte production, and embryo produced per oocyte collected. Furthermore, DIM and EP were not different between I:G quartiles when BCS £ 3.25. However, when BCS >3.25, DIM was higher for LI but only differed from HI (213 vs. 169 ± 15 d, respectively; P < 0.04); additionally, HI produced the most number of viable embryos, and LI the least number (0.9, 3.1, 5.7, and 1.6 ± 0.6 embryos for LL, LI, HI, and HH, respectively; P < 0.001). These data suggest that mid-to-high plasma insulin-to-glucose ratio enhances EP in lactating dairy cows with BCS >3.25 without affecting oocytes, mostly through insulin-dependent mechanisms.