By using household survey data, this paper examines the effect of legal knowledge, a proxy for farmers’ ability to protect their land, on agricultural development in rural China. The Ordinary Least Square (OLS) estimation results indicate that legal knowledge in a household raises agricultural production. Further, once the production effect of legal knowledge is controlled for, the objective measure of land expropriation has no production effect. These results survive for alternative measures of legal knowledge and subsample analysis. A two-stage least squares strategy further confirms that the effect of legal knowledge on farm production is causal. A preliminary channel analysis suggests that the impact of legal knowledge on farm production works mainly through farmyard manure investments and labor incentives.