The most common cause of Achilles tendon pain during walking is Achilles tendonitis, which is usually caused by an inflammatory reaction to the Achilles tendon and is aggravated by ankle extension and flexion activities. The Achilles tendon is a tendonous structure that migrates from the lower end of the gastrocnemius and hallux valgus muscles and ends at the heel tuberosity, which is the most important tendon in the back of the lower leg and controls the extension and flexion of the ankle joint. Most of the Achilles tendon pain is due to the gradual formation of aseptic inflammation after long-term acute and chronic strain of the Achilles tendon, which triggers local pain, especially when the pain is significantly aggravated by walking. The common clinical symptoms are pain over the heel, with significant localized pressure, increased pain with activity, and significant limitation of ankle extension and flexion. When Achilles tendonitis worsens, the tendon thickens, swells, and nodules can be palpated locally. Other causes of Achilles tendonitis include: 1. not adjusting the posture before exercise, and after repeated jumping movements, Achilles tendonitis can easily occur; 2. excessive exercise, resulting in strain on the Achilles tendon; 3. flat feet can significantly increase the chances of Achilles tendonitis. Because when walking, flat feet can lead to additional pressure on the Achilles tendon; 4, local injuries to the Achilles tendon caused by trauma, some of which are accompanied by local infection, resulting in pain.