The present study was carried out to assess the effect of gamma irradiation (0, 2, 4, 6, 8 and 10 kGy) and subsequent ambient storage conditions (12 months, 32 ± 2 °C) on physcico-chemical, antinutritional, functional, microbiological and sensory properties of brown rice based weaning food. The weaning food was prepared from brown rice, mungbean, apples, and walnuts. The amino acid contents of weaning food showed no clear trend of change with respect to increasing irradiation dose. Rehydration ratio (3.60–1.30%) and swelling power (2.59–1.08 g/g) of irradiated weaning food showed a significant decrease with increased dosage and storage time. The solubility index (1.32–6.18%) significantly increased with increased irradiation doses and storage period. Increased irradiation doses significantly decreased browning index (0.611–0.0.998), and moisture content (8.82–7.85%) while as storage period significantly increased browning index (0.611–0.998) and moisture content (7.85–8.82%) of weaning food. Irradiation doses and storage period showed a non-significant effect on the L* and a*colour values whereas, a significant effect was observed for b* values. Antioxidant activity, total phenol, β-carotene, iron, and calcium contents were improved with irradiation doses and decreased with storage periods. Total plate count, sensory characteristics, phytate, and oxalate contents decreased with an increase in irradiation dose.