Surgical site infections are one of the most important post-surgery complications. Antimicrobial prophylaxis has been used routinely in surgeries to reduce infection incidence. However, inappropriate selection of antimicrobial agents or dosing can develop antimicrobial resistance, serious adverse reactions and prolong hospitalization. Current study aimed to examine prophylactic antibiotic prescription in surgeries in a teaching hospital in Sari, Mazandaran and evaluate level of adherence to the international guidelines. Between January 2015 to May 2015, 104 patients in general surgery ward were selected and enrolled in the study. The prophylactic antibiotics, dosage, timing and duration of administration were collected by reviewing patients’ records and compared to the existing guidelines. Prophylactic antibiotic was given to 85.5% of patients. Prescribed antibiotics were cefazolin (46.1%), metronidazole (24%), ceftriaxone (12.5%), ciprofloxacin (1.9%) and vancomycin (0.96%). Most of the patients (62.9%) received an inappropriate and delayed timing. Proper antibiotic dosage was seen in 45.2% of patients. All patients received post-operative prophylactic antibiotic. Main antibiotics include cefazolin (41.3%), metronidazole (33.7%), ceftriaxone (31.7%) and clindamycin (20.2%). Only 10 (21.9%) patients received cefazolin or vancomycin for a total duration of 48 hours or less. Surgical wound infection occurred in 17 (16.3%) patients during hospital stay. Adherence to antimicrobial prophylaxis guidelines was completely achieved in 14.4% of cases. Results of this study signified that adherence to existing guidelines was poor and the most common mistakes were over usage, inappropriate dosage and choosing of antibiotics.