An optimal education subsidy formula is derived using an overlapping generations model with parental altruism. The model predicts that public education subsidy is greater in economies with lesser parental altruism because a benevolent government has to compensate for the shortfall in private education spending of less altruistic parents with a finite life. On the other hand, growth is higher in economies with greater parental altruism. Cross-country regressions using the World Values Survey for altruism lend support to our model predictions. The model provides insights about the reasons for higher education subsidy in richer countries.