To evaluate the psychometric properties of the Spanish version of the "FETCH-Q™", 228 dogs with cardiovascular diseases were included. After forward and back translation of the original questionnaire, nonexperts, ethologists and veterinary colleagues evaluated the content's validity through feedback. For criteria validity, the total score was correlated with the heart disease/failure class. For construct validity, the overall quality of life of the dog and the results obtained in each question was correlated. The reliability of the questionnaire was assessed using the Cronbach's alpha coefficient. To evaluate the test-retest validity the intra-class correlation coefficient and Wilcoxon signed-rank test were used. A good agreement with the original questionnaire was evident. For construct validity, the questionnaire obtained r > 0.09 to < 0.82. The criterion validity was appropriate and the correlation was rho = 0.82, with an effect size of 0.55 (P < 0.05). Cronbach's alpha coefficient was (α = 0.89). The test-retest assessment revealed adequate repeatability (correlation coefficient = 0.87; P < .001). There was no difference in the owner responses to the questionnaire at baseline and 2 weeks later in dogs with stable cardiac disease (P > .05). This study supports the validity of psychometric properties of the Spanish version of the functional evaluation of cardiac health questionnaire "FETCHSV2-Q™" to assess Health-related Quality of Life in dogs with cardiovascular disease in clinical settings and research.