Background and Objective: Nowadays, hypertension is the most common problem in developing countries. Compared to other determinant parameters of obesity, body mass index is a better predictor of cardiovascular risks. The purpose of this study was to determine the association between body mass index and systolic and diastolic blood pressure of students' parents in Khorramabad City.
 
Materials and Methods: This study was a cross-sectional, descriptive study. The statistical population consisted of all students’ parents in Khorramabad City, 211 of whom, applying cluster random sampling, were selected as a sample. Blood pressure, weight and height were measured and recorded with the similar equipment. The collected data was analyzed using Pearson correlation coefficient.
 
Results: In this study, 161 women and 50 men participated. Results indicated that the mean and standard deviation of systolic and diastolic blood pressures were 124.40±14.62 and 75.60±12.83 in women and 121.80±11.07 and 78.76±8.33 in men, respectively. Mean and standard deviation of body mass index were in men and women 26.52±4.09 and 28.80±4.25, respectively. There was a significant relationship between body mass index and systolic blood pressure in men and women (P=0.001, r=0.45 and P=0.009, r=0.20, respectively). Also, this relationship was significant in terms of diastolic blood pressure in men (P=0.001, r=0.51) but this relationship was not significant in women (P=0.688, r=0.03).
 Conclusion: Overall, findings showed that there is a positive and significant relationship between body mass index and blood pressure. Therefore, in order to prevent hypertension, it is recommended that people gain an appropriate weight in adulthood.