OBJECTIVE： To investigate the effects of etomidate combined with propofol on painless gastrointestinal endoscopy and cognitive function of elderly patients. METHODS： Totally 90 elderly patients with painless gastrointestinal endoscopy were randomly divided into propofol group （30 cases）， etomidate group （30 cases） and combination group （30 cases）. Propofol group was given Fentanyl injection 1 μg/kg+Propofol injection 1.5 mg/kg； etomidate group was given Fentanyl injection 1 μg/kg+Etomidate injection 0.3 mg/kg； combination group was given Fentanyl injection 1 μg/kg+Propofol injection 1 mg/kg+Etomidate injection 0.15 mg/kg. The levels of SBP， DBP， HR， MAP and SpO2 at different time points， examination time， anesthesia induction time， recovery time and recovery time of orientation were observed in 3 groups. NCSE and MMSE score at different time points， the occurrence of ADR were also observed in 3 groups. RESULTS： During examination， SBP， DBP， MAP and SpO2 of propofol group were significantly lower than before anesthesia， after examination and those of combination group， with statistical significance（P＜0.05）； but there was no statistical significance in above indexes of propofol group between during examination and before anesthesia（P＞0.05）. The recovery time and recovery time of orientation in combination group were significantly shorter than propofol group and etomidate group， with statistical significance （P＜0.05）， but there was no statistical significance in above indexes between etomidate group and propofol group （P＞0.05）. The proportion of patients’ memory ability， computing ability， orientation ability passing examination in combination group were significantly higher than propofol group， with statistical significance （P＜0.05）. There was no statistical significance in above indexes between combination group and etomidate group， between etomidate group and propofol group （P＞0.05）. There was no statistical significance in MMSE score of combination group at different time points（P＞0.05）； MMSE score of propofol group 15， 30 min after anesthesia and that of etomidate group 15 min after anesthesia were significantly lower before anesthesia and combination group， with statistical significance （P＜0.05）. There was no statistical significance in MMSE score of propofol group 1 h after anesthesia， etomidate group 30 min and 1 h after anesthesia， compared to before anesthesia （P＞0.05）. The incidence of apnea， hypotension and injection pain in combination group and etomidate group were lower than propofol group， the motor response， myoclonus， nausea and vomiting in combination group and propofol group were lower than etomidate group， the tachycardia ease in combination group was lower than propofol group， with statistical significance（P＜0.05）. CONCLUSIONS： Etomidate combined with propofol anesthesia shows good therapeutic efficacy for painless gastrointestinal endoscopy of elderly patient， can reduce cognitive dysfunction and shortens recovery time， but doesn’t increase the occurrence of ADR.