Background: Knee joint is the most frequently injured joint as it is more superficial and susceptible. Previously, clinical examination was the sole method used to diagnose various knee disorders. Later, MRI and Arthroscopy were introduced and suggested by many surgeons. Aims and Objectives: This study was conducted to analyze the correlation between all three methods in the diagnosis of internal derangement of the knee in a tertiary care centre. Methodology: A hospital based cross-sectional study conducted at a tertiary care centre in Rajahmundry, India, between January 2017 to December 2017 among 124 patients aged 18-60 years and with internal derangement of the knee. Results: Among 124 patients, 111 (89.52%) were males and 13 (10.48%) females. Right side 84 (67.74%) was affected more than the left side 40 (32.26%). Mean age of the patients was 31 years with maximum number of them within 20-40 years. The most common mode of injury was road traffic accident followed by sports injuries. Clinically, ACL was the structure most commonly involved followed by medial meniscus, lateral meniscus, PCL, medial collateral ligament and lateral collateral ligament. MRI also revealed similar hierarchy in the involvement of structures, while arthroscopy showed that medial meniscus was most commonly involved followed by lateral meniscus, ACL, PCL, medial collateral ligament and lateral collateral ligament. With respect to correlation between procedures, medial meniscus, lateral meniscus, anterior cruciate ligament, posterior cruciate ligament and lateral collateral ligament injuries could be detected better by combined MRI and Arthroscopy, with Spearman’s rho being 0.671, 0.499, 0.477, 0.385 and 0.383 respectively and significant ‘P’ value (0.000). However, medial collateral ligament injuries could be detected better by combined clinical examination and MRI (Spearman’s rho 0.352 and ‘P’ 0.000). Conclusion: The sensitivity and specificity of MRI with Arthroscopy were higher for the diagnosis of internal derangements of knee, in comparison to the sensitivity and specificity of Clinical examination with Arthroscopy. However, Clinical examination is still dependable whenever possible. Keywords: Correlation, Clinical, MRI and Arthroscopy internal derangements of knee, India