The fastest medical evaluation possible is deemed vital to assuring the best possible care for critical patients, several diagnostic tests are necessary to fully evaluate these patients because care decisions will often be based on the results, using a functioning peripheral venous catheter for obtaining blood samples helps patients, medical and nursing staff. Objective: The objectives of this study were to compare between obtaining blood samples from peripheral intravenous catheters and venipuncture on complete blood count and glucose. Tools and methods: This study was conducted on a sample of 80 patients, was selected by simple random sampling who are employing in surgical yard in Al-Asad University hospital, and obtains double blood specimens by two methods (Peripheral venous catheters,venipuncture) and applying the same laboratory studies on it. Results: The results showed that obtaining blood samples from peripheral venous catheters is acceptable method for (WBC, RBC, HGB, HCT) where the value (0.05< P) and unacceptable method for (PLT, GLU) where the value (0.05> P).