CONTEXT: Existing guidelines often lack sex-specific prevention strategies for type 2 diabetes mellitus (T2DM). Life's Essential 8 (LE8) highlights the role of health behaviors in influencing cardiovascular health (CVH). Due to inherent sex differences, the impact of CVH on T2DM risk may vary between men and women, especially across menopausal stages. OBJECTIVE: The purpose of this paper is to explore sex-based differences in CVH and the incidence of T2DM among women at different menopausal stages and men. METHODS: A prospective cohort study was conducted, involving 126 818 participants without preexisting T2DM from the UK Biobank. CVH was assessed using the LE8. Absolute risks (ARs) and hazard ratios (HRs) were separately employed to assess the association between increased CVH and T2DM risk. The accelerated failure time model assessed the effect of CVH on the time to T2DM onset. RESULTS: Over a mean follow-up of 168 months, 4315 cases of T2DM were documented. In men, each 1-point increase in CVH was associated with a 0.268% decrease in AR and a 6.4% decrease in HR for T2DM. In premenopausal, perimenopausal, and postmenopausal women, each unit increase in CVH resulted in a 0.105%, 0.180%, and 0.166% decrease in AR and a 7.7%, 5.2%, and 6.4% decrease in HR of T2DM. The adjusted median time to T2DM onset was delayed by 12.46, 9.83, 11.5, and 21.43 months in the highest quintile of men, premenopausal, perimenopausal, and postmenopausal women, respectively, compared with the lowest CVH quintile. CONCLUSION: As CVH improved, the reduction in AR for T2DM was more prominent in men than in women. HR trends for CVH and T2DM were similar in men and postmenopausal women. Increased CVH delayed the onset of T2MD both in men and women, with the most significant delay observed in postmenopausal women.