Objective: The purpose of this study is to evaluate the effects of taking low doses of omega-3 (1,5 g/day) in hypertensive women. Method:Longitudinal clinical trial Health Center of San Fernando de Badajoz. Primary care. 55 postmenopausal hypertensive women. For the study, participants were divided into two groups, group supplementation (GS) (n=28) and one control group (CG) (n=27). Supplementation with n-3 PUFA to the experimental group for 6 months (1.5 g/day). The control group was given nothing. The variables of the study have been blood pressure, n-3 fatty acid supplementation and it was tried to control nutritional intake. Results:In SG, systolic blood pressure decreased significantly at the third (p<0.001) and sixth (p<0.001) month after starting the study, and three months (p<0.01) since the end of supplementation. With regards to diastolic blood pressure levels in the same group, also produced a decrease that became significant (p<0.01) after six months of supplementation and maintained at three months of concluding the supplementation, even without acquire statistically signification. We have shown increases in the plasma percentages of fatty acids C20:5n3 and C22:6n3, after three months of initiating supplementation (p<0.05), after 6 months of it (p<0.001) and in three months of leaving supplementation (p<0.001). Arachidonic acid decreases throughout the supplementation period and this reached a statistically significant difference after 6 months within supplementation. Conclusions:The intake of 1.5 g/day of fish oil as coadjuvant in the treatment of all kinds of arterial hypertension improves blood presure and other cardiovascular diseases.