This study aims to assess the changes in blood pressure (BP) and its highest value, mean arterial pressure (MAP), and heart rate (HR) with the 15 degree leg raising position in the patients with cardiovascular disease (CVD) who were admitted in the intensive care unit. In this quasi-experimental cohort study, one group posttest-only design was used in which thirty two subjects were selected by using the G* power 3.1.9.2 analysis program. The main reason for applying the 15 degree leg raising position was with the expectation of the elevation of the BP in patients with CVD, who showed temporarily low BP. Using the SPSS/WIN 23.0 program, the data was analyzed for descriptive statistics, paired t-test, and repeated measured ANOVA. The intervention of the 15 degree leg raising position showed no significant difference with HR, but indicated a meaningful difference with systolic BP and MAP. The 15 degree leg raising position proved to be a useful intervention to only the patients with CVD whose BP was instantly lowered. Thus, this study suggests a follow-up study for the various degree leg raising positions and the changes in BP and its highest value, MAP, and HR depends on degrees. Non CVD subjects might involve the intervention as well.