BACKGROUND Elderly are more exposed to cognitive impairment due to the presence of underlying disease and some structural and functional changes in the nervous system. The aim of this study is to compare the effects of two drugs of Etomidate and Propofol on haemodynamics, delirium and dementia of elderly patients after orthopaedic surgery. METHODS In this nonrandomized controlled clinical trial, with the use of sample size formula, 100 patients over 60 years of age who had undergone orthopaedic surgery under general anaesthesia referred to Rafsanjan Ali-Ebn-Abi-Taleb Hospital in 2018 were enrolled in the study by convenience sampling method. After obtaining informed consent, participants were divided into two groups: A) Propofol (2 mg/Kg) and B) Etomidate (0.2 mg/Kg) for induction of anaesthesia. Haemodynamic parameters (heart rate, blood pressure, arterial oxygen saturation, amount of bleeding) and cognitive impairment were measured 1 hour before surgery, one day and three days after surgery by MMSE (for checking dementia) and NEECHAM scale (for evaluation of delirium levels). Data was analysed using Independent T-test and chi-square test. The significance level of the tests was considered to be equal to or less than 0.05. RESULTS Of the 100 patients under study, 56 (56%) were male and 44 (44%) were female. Hemodynamic change in propofol group was significantly higher than Etomidate group (p= 0.001) .The amount of bleeding in Propofol group was significantly lower than Etomidate group (p= 0.047). On the first day after surgery, the mean of MMSE score (representing dementia) in the Propofol group was lower than in the Etomidate group (p=0.043) and on the third day after surgery it was more than Etomidate group (p = 0.002). On the first day after surgery, the level of delirium in the Propofol group was lower than Etomidate group significantly (p<0.05). CONCLUSIONS The results of this study indicate that the use of Propofol for orthopaedic surgery in elderly patients decreases the chance of delirium and increases the amount of bleeding.