People’s social and political opinions are grounded in their moral concerns about right and wrong. We examine whether five moral foundations—harm, fairness, ingroup, authority, and purity—can influence political attitudes of liberals and conservatives across a variety of issues. Framing issues using moral foundations may change political attitudes in at least two possible ways: (a) Entrenching: Relevant moral foundations will strengthen existing political attitudes when framing pro-attitudinal issues (e.g., conservatives exposed to a free-market economic stance) and (b) Persuasion: Mere presence of relevant moral foundations may also alter political attitudes in counter-attitudinal directions (e.g., conservatives exposed to an economic regulation stance). Studies 1 and 2 support the entrenching hypothesis. Relevant moral foundation-based frames bolstered political attitudes for conservatives (Study 1) and liberals (Study 2). Only Study 2 partially supports the persuasion hypothesis. Conservative-relevant moral frames of liberal issues increased conservatives’ liberal attitudes.