Osteoarthritis (OA) is the most common degenerative joint disease and affects millions of people worldwide. Signal pathways triggered by biomechanical stimuli play an important role in the initialization and progression of OA, via direct physical effects and inflammation factors. Diagnosis of OA is currently based on radiological and clinical findings, typically when the disease is at a late stage. In recent years, Raman spectroscopy has emerged as a suitable technique for the study of OA, providing useful information about the subtle molecular and biochemical changes that occur in joint tissues during the progression of the disease. Studies also show the great potential of Raman methods for the early detection of the disease. In this review, we present the advances in the assessment of OA by means of Raman spectroscopy.