Prostate cancer mortality-to-incidence ratios (MIRs) are associated with the level of available healthcare. However, no data are currently available to show an association between differences in the prostate cancer MIRs and healthcare disparity. In the present study, changes in MIR over time (δMIR) were calculated as the difference between MIRs in 2018 and 2012. The significance between expenditures on healthcare and the human development index (HDI) were analyzed using Spearman's rank correlation coefficient. A total of 47 countries were studied. Countries were excluded based on inadequate data quality and missing data. The crude prostate cancer incidence rates, but not mortality rates, correlated with the HDI score and healthcare expenditure. A high HDI score and high healthcare expenditure were also significantly associated with a favorable MIR (ρ = -0.704, p < 0.001; ρ = -0.741, p < 0.001, respectively). Importantly, healthcare disparities were negatively associated with the improvement in δMIR (ρ = -0.556, p < 0.001; ρ = -0.506, p < 0.001, respectively). These findings indicate that favorable prostate cancer MIRs are associated with higher healthcare expenditures, but the trends in MIR between 2012 and 2018 correlate negatively with HDI and healthcare expenditure.