Background: Spinal anesthesia is a widely used technique for surgery in the elderly. Due to its efficacy, rapidity, reduction of blood loss, and protection against thromboembolic complications. However, associated with exaggerated responses to conventional doses of local anesthetics in elderly patients; thereby increasing hemodynamic complications and as high as 50% hypotension incidence in this patients. An alternative method has been designed to minimize these unwanted hemodynamic effects by administration of adjuvants with low dose of local anesthetics.rnObjective: To compare the effectiveness of low dose bupivacaine with fentanyl versus normal dose bupivacaine alone on hemodynamic response, onset and duration of block and complication in elderly patients who undergo lower extremity Orthopedics surgery under spinal anesthesia at Tikur Ambessa Specialized Hospital from November, 2018 - April, 2019rnMethods: prospective cohort study design was employed on a total of 64 elderly lower extremity orthopedics procedures, non-exposed group (Group B) received 15 mg of 0.5% isobaric bupivacaine alone and study group (group BF) taken 10mg of 0.5% isobaric bupivacaine with 25mcg of fentanyl to see the effect on hemodynamic changes after spinal anesthesia. SPSS version 25 used for analysis, normality of distribution for continuous variable was tested by Shapiro-Wilk test then parametric data was analyzed by using independent t-test and nonparametric data by Mann-Whitney U-test and categorical data by using chi-square test and fisher exact test. The level of statistical significance for all tests taken P < 0.05.rnResults: The incidence of hypotension after spinal anesthesia was higher in group B than group BF) (37.5% vs. 9.4%), respectively: p=0.008) and Group BF showed better hemodynamic stability. Considerable difference was noticed in intravenous fluid consumption between groups, group B (1420Â±97ml) and group BF (1215Â±94ml) having (p