To evaluate the effect of Life's Essential 8 (LE8), a comprehensive cardiovascular health (CVH) metric from the American Heart Association, on the risk of cardiac conduction disorders (CCD). We conducted a prospective cohort study of 112,160 adults from the UK Biobank, free of cardiovascular disease at baseline, to examine the association between LE8 scores and the risk of CCD. LE8 scores were categorized into low (0-49), moderate (50-79), and high (80-100) CVH groups. Cox proportional hazards models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) for CCD incidence during a median follow-up of 11.6 years. A total of 2,760 CCD cases were identified. After adjustment for confounders, the high CVH group exhibited a significantly lower risk of CCD compared to the low CVH group (HR: 0.48, 95% CI: 0.40-0.56). Further analyses showed reduced risks for both severe conduction block (HR: 0.63, 95% CI: 0.52-0.78) and left bundle branch or fascicular block (HR: 0.35, 95% CI: 0.25-0.49) in the high CVH group. Restricted cubic spline regression revealed an L-shaped association between LE8 score and CCD risk. Among individual LE8 metrics, WQS analysis revealed that BMI and sleep health were the major contributors to reduced CCD risk. Higher LE8 scores were associated with a lower risk of CCD, including severe conduction block requiring pacemaker implantation and left bundle branch or fascicular block. Comprehensive strategies targeting optimal CVH, especially BMI and sleep health, may be beneficial for preventing CCD.