Aim: The aim of this study was to evaluate the differences between the useof the dexamethasone sodium phosphate and the use of diclofenac sodiuminjection into the masseter muscle to relief the pain following surgicalremoval of impacted lower third molar.Materials and Methods: The present study was conducted on 30 patients.All the impacted teeth were limited to (mesioangular or vertical, class1 orclass2, position A or position B). Patients grouping:Group (I): Injection of asingle dose 8mg Dexamethasone into the masseter muscle via an intraoralapproach immediately after the surgery.Group (II): Injection of a single dose75mg Diclofenac sodium into the masseter muscle. Postoperativerecording:Pain intensities were evaluated by a visual analogue scale (V.A.S).Results:Trismus subsided in all cases of Dexamethasone group within 7days (1 week) while in Declofen group; 5 cases subsided within 2 weeks and10 cases subsided within 3 weeks.Edema subsided in all cases ofDexamethasone group within 7 days (1 week) while in Declofen group; 3cases subsided within 1 week, 10 cases subsided within 2 weeks and 2 casessubsided within 3 weeks.Conclusions: The results had proven that local intramuscular injection ofdexamethasone (group I) into masseter muscle was superior to declofenac(group II) into the same muscle concerning edema and trismus. Declofenacsodium was superior than dexamethasone sodium phosphate in early controlof pain.