The aim of the study was to test whether a screening navigation program leads to more favorable health beliefs and decreases social inequalities in them. The selected 261 noncompliant participants in a screening navigation versus a usual screening program arm had to respond to health belief measures inspired by the Protection Motivation Theory. Regression analyses showed that social inequalities in perceived efficacy of screening, favorable attitude, and perceived facility were reduced in the screening navigation compared to the usual screening program. These results highlight the importance of health beliefs to understand the mechanism of screening navigation programs in reducing social inequalities.