OBJECTIVE. We sought to investigate whether occupational therapy that includes adjusting the challenge–skill balance improves health-related quality of life (HRQOL) for older adults in comparison with standard occupational therapy.

METHOD. In this single-blind, randomized controlled trial, 56 older adults were assigned to two groups that received 10 sessions of occupational therapy with and without adjustment of challenge–skill balance. The primary outcome was change in HRQOL after 10 sessions of occupational therapy.

RESULTS. Significant differences were observed in HRQOL using the EuroQol–5 Dimension score (p = .022, d = 0.76) and the eight-item Short-Form Health Survey scores for general health (p = .001, d = 0.99) and in flow experience using the Flow State Scale for Occupational Tasks (p = .008, d = 0.82).

CONCLUSION. Assessment and adjustment of the challenge–skill balance of activities may effectively improve older adults’ HRQOL.