The aim of this study was to assess the outcome of arthroscopic lunate fossa resection arthroplasty for patients with Kienböck's disease, previously managed without operation, and a non-functional lunate fossa. For adult patients with relapse or exacerbation of pain from Kienböck's disease 2 years after the onset of symptoms, arthroscopic removal of lunate fossa cartilage was performed to reach bleeding bone, if the cartilage in the lunate fossa was non-functional and the scaphoid fossa was intact. Sixteen patients (mean age 35 years; range 27-56) were included. At a mean follow-up of 39 months (range 24-64), the preoperative mean visual analogue pain scale and QuickDASH score decreased from 7 (SD 2.2) and 50 (SD 16) to 1.4 (SD 1.6) and 13 (SD 9.6), respectively. A minor deterioration in mean radioscaphoid angle and carpal height ratio occurred. Arthroscopic lunate fossa resection arthroplasty is a viable option for selected patients with Kienböck's disease.Level of evidence: IV.