The authors use data from the Health and Retirement Study's Earnings Benefit File, which links Health and Retirement Study to Social Security Administration records, to estimate the impact of childhood health on earnings curves between the ages of 25 and 50 years. They also investigate the extent to which diminished educational attainment, earlier onset of chronic health conditions, and labor force participation mediate this relationship. Those who experience poor childhood health have substantially diminished labor market earnings over the work career. For men, earnings differentials grow larger over the early to middle career and then slow down and begin to converge as they near 50 years of age. For women, earnings differentials emerge later in the career and show no evidence of convergence. Part of the child health earnings differential is accounted for by selection into diminished educational attainment, the earlier onset of chronic disease in adulthood, and, particularly for men, labor force participation. (Contains 3 figures, 3 tables and 6 notes.)