Resumen: The high incidence of non-desired part-time jobs and temporary contracts after the Great Recession has become one of the most important drivers of the outstanding rise in income inequality in Spain during the last decade. We explore the determinants of involuntary part-time work in Spain over the period 2006-2014 and find that gender has a large, significant and robust positive effect on having that employment status, even after controlling for the type and duration of contracts, type of activity or occupation. A female worker is about7.4-8.3 percent more likely to have a non-desired part-time job than a male worker with the same characteristics. Moreover, working in the Public Administration or having a temporary contract increases this probability over 10 percentage points. The results highlight the persistent precariousness of the employment recovery in Spain and the need of a careful reflection on the next labor market reform.