Because the two main models and instruments used to evaluate psychosocial factors at work were developed and applied primarily in developed countries, there are still questions about their properties in less economically developed countries. In this study, a Spanish version of the Job Content Questionnaire (JCQ) was tested in Colombia. Cross-sectional studies, with self-administered surveys, were performed among 294 nurses, 281 bus drivers, and one mixed occupational group with 661 participants. Means and standard deviations among Colombian workers were compared against each other and with averages from studies in other countries. The internal consistency was analyzed through the Cronbach alpha coefficient; the factorial validity through exploratory factorial analysis; concurrent validity of the instrument was calculated using correlations with the effort/reward ratio of the ERI Questionnaire; the predictive validity was tested using correlations with one indicator of health. Differences between samples were generally small, but some interesting tendencies could be observed. The Cronbach�s alpha coefficients were generally acceptable. Difficulties with three items (JCQ 2, 6 and 14) were found. The factor analyses indicate that the best factorial solution has seven factors. The most problematic factor seems to be �decision latitude�. Some items have inconsistent loadings and reliability problems. Most of the JCQ scales were correlated with the health indicators in the expected direction. Finally, the �job strain� indicator and the effort/reward ratio were positively correlated. It was concluded that the Spanish version of the JCQ is an acceptable instrument to assess psychosocial risk factors among workers in Colombia.