Onion is one of the world's most valuable vegetable crops known for its pungent flavour and is a staple in many cuisines around the world. The aim of onion bulb storage is to meet customer demands and extend the supply of onions over the year, while maintaining product quality. Hence, the current study was carried out with the objective of examining the various storage methods for producing quality onions and enhancing shelf life of aggregatum onions. Studies were conducted to observe the effects of different storage structures, viz., natural ventilated storage structure and forced ventilated storage structure under ambient conditions for 90 days. The physical and biochemical characteristics of preserved onions were tested for quality during the study. The forced ventilated storage structure proved to be more efficient in delivering the optimal situation for onion bulbs during the 90-day storage period. In naturally ventilated storage structure, the onion had a physiological weight loss of 34.47–35.10 % whereas in forced ventilated storage the loss was reduced to 25.23 %. As a result, this study concluded that the structure ventilated from all sides is more capable of preventing onion bulb deterioration and losses during storage.