The use of analgesics to alleviate the severe pains associated with many diseases is necessary. It is therefore important to study the effects of administration these analgesics to determine the side effects for their use. Hence we decided to study the hematological and biochemical effects of tramadol and tramadol withdrawal on male albino rats. Rats were divided into four control rat groups (7 rats each), and four tramadol rat groups (7 rats each); two groups administrated a daily oral dose of tramadol (20 mg/kg b.wt) for 30 and 60 days and two groups also administrated a daily oral dose of tramadol for 30 and 60 days then tramadol withdrawal for 7 days. Hemoglobin (Hb) content, red blood cells (RBCs) count, hematocrit (Hct) value, and lipid profile decreased, while white blood cells (WBCs) and platelets counts, liver function enzymes, and kidney function parameters increased after tramadol administration. Most parameters improved after tramadol withdrawal. The study showed the harmful effects of tramadol on the hematological and biochemical parameters and the effects of improvement on rats after tramadol withdrawal from them, especially after a short period.