Introduction: Chondromalacia of the trochlear notch and stress fracture of olecranon are uncommon injuries in the throwing athletes. Materials and methods: We report an 18-year-old high school pitcher who had persistent postero-lateral elbow pain after a healed olecranon stress fracture of the right elbow. Diagnostic arthroscopy revealed chondromalacia of the trochlear notch. Results: After treatment with arthroscopic drilling and abrasion chondroplasty, he returned to competitive pitching 1 year later postsurgery. This rare association between chondromalacia and stress fracture of the olecranon has not been reported previously in the literatures. Conclusion: Chondromalacia of the trochlear notch should be included as a differential diagnosis in evaluating athletes with persistent elbow pain after healed olecranon stress fractures.