Introduction: Myofascial Pain Dysfunction Syndrome (MPDS) is one of the most important causes of the orofacial pain. The main purpose of this study was to evaluate 40 related variables in this regard. Materials and Methods: Thirty nine patients with MPDS were evaluated in this study. Different factors including age, gender, occupation, marital status, sensitivity of masticatory muscles, maximum opening of the mouth, deviation, deflection, involvement of temporomandibular joint, habit, parafunction, malocclusion, neck pain, headache, earache and history of jaw involvement, etc were analyzed in this evaluation. Results: In our study, 39 patients (32 females and 7 males), 20-40 years old, with the average age of 35±13.32 years were studied.51% were housewives and 74.4% were married. The most common involvements were Clicking (74.4%), pain in temporomandibular joint (54%), headache (46.2%), earache (41%), neck-pain (35.9%), trouble in the mouth opening (71.8%), malocclusion Class I (74.4%), cross bite and deep bite (25%), clenching (64.1%) and involvement of masseter and lateral pterygoid muscle (84%). Conclusion: Since MPDS consists of variable symptoms, it might be very difficult to provide any definite diagnosis and treatment. Therefore the more the specialists extend their knowledge and information about this disorder, the more they will make the best decision in this regard.