OBJECTIVES: To investigate the efficacy of adding radial extracorporeal shockwave therapy or sham to exercise for people with insertional Achilles tendinopathy. DESIGN: A two-armed, parallel-group, explanatory, single-centre, randomised controlled trial within a superiority framework. SETTING: Private clinic. PARTICIPANTS: People diagnosed with insertional Achilles tendinopathy who were over 18 years old with a symptom duration of greater than 3 months. INTERVENTION: A total of 76 people were randomly assigned (one-to-one ratio) to receive three sessions of radial extracorporeal shockwave therapy or sham to the affected side (or most affected side if bilateral). All participants received identical education and exercise. OUTCOME MEASURES: The primary outcome was the Victorian Institute of Sports Assessment - Achilles questionnaire. Measures were recorded at baseline, 6 weeks and 12 weeks. RESULTS: At 12 weeks, the questionnaire data were available for 37 people (96%) in the radial extracorporeal shockwave therapy group and 36 people (95%) in the sham group. For the primary outcome, we found no evidence for between-group differences at 6 (3, 95% confidence interval -4.6-10.5) or 12 weeks (4.6, 95% confidence interval -2.5-11.6). There was also no evidence for a between-group difference for any secondary outcome measures at either 6 or 12 weeks ( CONCLUSION: The addition of radial extracorporeal shockwave therapy to exercise and education did not lead to improvements in pain, function or other outcomes compared to sham at 6 or 12 weeks among people with insertional Achilles tendinopathy.