The present investigation was carried out to study the influence of the IAA application on fruit set in bell pepper (Capsicum annuum L.). Two cultivars viz, hybrid Indra and variety Royal Wonder were selected for the study during 2015-16. Four concentrations of IAA i.e. @ 50, 100, 150, 200 µg ml-1 were applied as foliar application at green bud stage and before the onset of high temperature. Various morpho-physiological, biochemical and yield attributing parameters were recorded between 40 to 80 days after transplanting (DAT). Improvement in growth in terms of plant height, plant spread, leaf area, chlorophyll and carotenoid content, level of total soluble sugars, proteins, phenol and proline content was recorded in treated plants as compared to controls. Application of IAA resulted in reduced lipid peroxidation in leaf tissue. Cellulose activity in pedicel of flowers was also found to decrease with IAA which resulted in less abscission of flowers in treated plants. Pollen viability and fruit set percent also showed an improvement due to IAA treatment. Average fruit weight and fruit yield were also enhanced due to increase in fruit set percent. 100 µg/ml IAA application in hybrid Indra and 200 µg/ml IAA application in variety Royal Wonder proved to be most effective.