Depression constitutes a major public health problem due to its high prevalence and difficulty in diagnosis. The Hopkins Symptom Checklist-25 (HSCL-25) scale has been identified as valid, reproducible, effective, and easy to use in primary care (PC). The purpose of the study was to assess the psychometric properties of the HSCL-25 and validate its Spanish version. A multicenter cross-sectional study was carried out at six PC centers in Spain. Validity and reliability were assessed against the structured Composite International Diagnostic Interview (CIDI). Out of the 790 patients, 769 completed the HSCL-25; 738 answered all the items. Global Cronbach’s alpha was 0.92 (0.88 as calculated for the depression dimension and 0.83 for the anxiety one). Confirmatory factor analysis (CFA) showed one global factor and two correlated factors with a correlation of 0.84. Area under the curve (AUC) was 0.89 (CI 95%, 0.86–0.93%). For a 1.75 cutoff point, sensibility was 88.1% (CI 95%, 77.1–95.1%) and specificity was 76.7% (CI 95%, 73.3–79.8%). The Spanish version of the HSCL-25 has a high response percentage, validity, and reliability and is well-accepted by PC patients.