PURPOSE: This study was performed to determine the involvement of joints by screws, inserted on the anterior process of the calcaneus, using cadaveric specimens. MATERIALS AND METHODS: An L-shaped lateral incision was performed on 32 embalmed feet (16 cadavers). An H-plate was applied on lateral wall of the calcaneus and it's anterior margin was located at 4 mm posterior to the lateral margin of the calcaneocuboidal joint. 3.5 mm cortical screws were inserted perpendicularly to the lateral calcaneal wall through the plate. Each calcaneus was dissected and taken out from the foot, and whether the tips of screws penetrated joints on the anterior process was evaluated. RESULTS: 11 (17.2%) of 64 screws, inserted on the anterior process, penetrated joints. Among them, seven screws involved the calcaneocuboidal joint and four screws penetrated the anterior facet of the subtalar joint. In two cases, both joints were penetrated by screws. CONCLUSION: This study shows that joint surfaces could be penetrated by screws inserted from the lateral surface on the anterior process of the calcaneus. Care should be given to selecting the length and insertional angle of screws. Intraoperative radiography would be needed to observe the articular surface on the anterior process, when screws were inserted to the anterior process close to the calcaneocuboidal joint.