The psychometric characteristics of the Impact of Weight on Quality of Life – Lite (IWQOL-Lite) questionnaire have been adequately evaluated in samples of North American people. Objective: to evaluate the reliability and validity of a Spanish version of the IWQOL-Lite questionnaire to measure health-related quality of life (HRQL) in patients from Reina Sofia Clinic in Bogota. Design: descriptive, cross-sectional study. Methods: internal consistency reliability and test-retest reliability were evaluated. Evidence of validity was obtained from exploratory factor analysis and correlational studies with collateral measures. Subjects: 223 subjects (154 women), average age 49.4 years, average body mass index 33.3 kg/m2, with one or more obesity-related comorbid diseases. Results: Cronbach’s alpha coefficient was between 0.89 and 0.96 for the five questionnaire’s subscales. For test-retest reliability, intraclass correlation coefficient was between 0.85 and 0.94. Data compatible with a five-factor structure was found by exploratory factor analysis, which correspond with the original design. Correlation coefficients greater than 0.4 were obtained between IWQOL- Lite measures and those of SF-36. Negative correlation coefficients greater than -0.5 were found with anthropometric obesity measures. Conclusion: reliability and validity of this version of the IWQOL-Lite questionnaire are adequate to measure HRQL in this group of patients.