Lactuca serriole. L. is commonly used traditionally as medicine for the therapeutical purposes of different conditions, including digestive, respiratory, and other conditions regardless of its neurotoxicity. Therefore, the study was undertaken to estimate the effect of the alcoholic extract Lactuca serriola. L. on brain and behavior. Thirty male rats were used. The rodents were divided into five groups: the first group without treatment; the second, third, fourth, and fifth group received dosages of 100, 200, 400, and 800 mg/kg b. w. of Lactuca extract via oral administration, respectively for fourteen days. The record of behavioral data was started after allowing the rats to explore freely for 10 minutes. To collect the data, the scan sampling method was used at one-minute intervals for twenty-eight hours in fourteen consecutive days, morning one hour and evening one hour. The effect of time on the behaviors was also evaluated. Results revealed that the dosages of 100, 200, and 400 mg/kg b. w. decreased running (walking) and climbing behaviors, on the other hand, improved rearing, paws licking, and grooming behaviors which indicates reduced stress in the rats. The dose of 800 mg/kg b. w. increased immobility and immobile sniffing, which affected the mood and central nervous system of the rats, especially the brain. Time also affected on behavioral components of all groups especially group 5. The study results suggest the range of phenolic dosages (100-400 mg per kg body weight) of Lactuca are harmless to use in animals experimentally without any toxicity and behavioral changes.