Epicondylitis, as a tendinopathy characterized by fibroblast and microvascular hyperplasia, is a common musculoskeletal problem especially related with repetitive hand and wrist motion. It has a prevalence of between 0.2% and 5% in general population depending on the amount of exposure to manual labor jobs. Although it is known that the pathological lesions lie in the flexor or extensor common tendons, there could be collateral ligament lesions and/or reactive synovitis accompanied, which may make a case unresponsive to the treatment aimed only at the tendinopathy. Epicondylitis is easy to diagnose with typical pain, tenderness, and positive provocation tests. However, many conditions can mimic epicondylitis that further imaging or electrodiagnostic studies should be undertaken to exclude other possible problems. Ultrasonography provides information about the existence and extent of tendinopathy with relatively high specificity. Magnetic resonance imaging is often required to rule out other problems and confirm the diagnosis of the cases intractable to long term treatment. Many options of treatment are available for epicondylitis while numerous conflicting evidences have been noted, debating one treatment method is better than the others. Since it was reported that over 80% of epicondylitis improved within a year no matter what was done as treatment, it is a challenge to make accurate diagnosis and combine effective therapeutic regimens for the 20% of intractable cases.