[Purpose] This study developed heel support banding (HSB) using an elastic band for flexible heel support and investigated its effect on chronic Achilles tendon pain of a mountaineer. [Subject] A 40-year-old male mountaineer with chronic Achilles tendon pain [Methods] Ankle dorsiflexion and plantar flexion angles, VISA-A questionnaire, load-induced pain, total pain threshold and tenderness at 3 kg of pressure were measured before and after applying HSB. [Results] After one month of applying HSB, the dorsiflexion and plantar flexion angles increased; the VISA-A questionnaire score increased; the load-induced pain assessment score decreased; the pain threshold increased; and tenderness at 3 kg decreased. [Conclusion] These results indicate that HSB use improves ankle range of motion, decreases pressure and pain, and could provide a new approach for effective intervention and management of chronic Achilles tendon pain.