Internal derangement of the temporomandibular joint is defined as an abnormal position of the articular disc in relation with mandibular condyle and articular eminence presenting as disc displacement with or without reduction. This study was conducted on thirty patients diagnosed with Internal derangement of TMJ consisting of 8 males and 22 females averaging 34.6 years. Two groups Conventional Arthrocentesis (Group A) and Level 1 Arthroscopy (Group B) consisted of 15 cases each divided alternately. Clinical evaluation parameters included VAS for pain, maximal interincisal opening, deviation on mouth opening, range of motion including lateral excursion & protrusion movements recorded at 1 week, 1 month & 6 months postoperatively. Wilke's Staging according to MRI findings was recorded preoperatively and 6 months postoperatively. At 6 month follow-up, average reduction in VAS for pain & deviation on mouth opening was 72.43% & 24.73% in Group A and 77.66% & 65.41% in Group B, respectively. Average increase in MIO, right & left excursion & protrusion movements was 29.55%, 31.33%, 20.12% & 32.45% in Group A and 34.94%, 41.37%, 39.29% and 36.51% in Group B, respectively. Improved results were obtained clinically for all Wilke's stages in both groups with more number of patients improving in Group B. On comparing results, improvement was observed in various clinical evaluation parameters of both the groups at 6 months follow-up. However, statistically significant & better results were obtained for the Arthroscopy group.