The current study was aimed to investigate the effect of acetylsalicylic acid on pigeon birds. For this purpose healthy pigeons of different weights were randomly selected from Bio-Park University of Malakand and then placed it in different groups on the basis of their weighs. To observe the effect, different doses of acetylsalicylic acid were administered orally to each group of pigeons except one group which was kept as unmedicated (control group). Blood samples were collected from individual pigeon of each group periodically i.e. before medication, during medication and after medication and were analyzed for glucose, cholesterol, alanine amino tranferase (ALT) and uric acid. Blood hematology was also performed for each individual pigeon from all the groups. A significant decrease was observed in glucose and ALT level, while the cholesterol and uric acid level was increased. Likewise to glucose, reasonable increase was observed in total red blood cells count (TRBCs), Hematocrit value (HCT), Mean corpuscular volume (MCV), Mean corpuscular hemoglobin (MCH), Mean corpuscular Hemoglobin concentration (MCHC) and platelets count, while the Hemoglobin (Hb%) and total leukocyte count (TLC) level was decrease. Overall huge toxic effect of acetylsalicylic acid was recorded in pigeons; therefore it should be used carefully in veterinary medicines especially for the treatment of temperature and pain in game birds.