Background Extracorporeal shock wave therapy (ESWT) has been used as a safe alternative treatment for refractory musculoskeletal diseases, such as plantar fasciitis, Achilles tendinopathy and gluteal tendinopathy, and various forms of fibromatosis including palmar or penile fibromatosis. However, there is limited published data for clinical and sonographic features of plantar fibromatosis after ESWT. The purpose of this study was to evaluate the long-term clinical outcome of ESWT in ultrasonography-confirmed plantar fibromatosis and ultrasonographic changes of plantar fibroma after ESWT. Methods Medical charts of 26 patients (30 feet) with plantar fibromatosis confirmed by ultrasonography were reviewed. Finally, a total of 10 feet who underwent ESWT for "Poor" or "Fair" grade of Roles-Maudsley Score (RMS) and symptoms persisted for >6 months were included in this study. Short-term follow-up was conducted one week after ESWT and longterm follow-up time averaged 34.0 months. The Numerical Rating Scale (NRS) and RMS were collected for the evaluation of clinical features. Follow-up ultrasonography was conducted at long-term follow-up and changes of plantar fibroma was assessed. A greater than 50% reduction in the NRS and achievement of a "good" or "excellent" grade in the RMS were regarded as treatment success. Additionally, medical charts of 144 patients (168 feet) with plantar fasciitis confirmed by ultrasonography were reviewed and subsequently, 42 feet who underwent ESWT with the same protocol were included for the comparison of clinical features. Results In plantar fibromatosis, baseline NRS (6.2 ± 1.3) and RMS (3.5 ± 0.5) were significantly improved at short-term follow-up (NRS, 1.8 ± 1.0; RMS, 2.0 ± 0.8, P < .001, respectively)