In India onion is produced in three season’s kharif, latekharif and rabi, in which rabi harvest have good keepingquality and can be stored for longer period up to 5-6 months.Over a period of storage, there is a gain of three to fourtimes profit in market due to non-availability of onion.Hence, the storage of onion is very essential to maintainregular supply to the consumer till November. Due toimproper storage, more losses arise in farmer’s storagemethod due to higher sprouting, rotting and physiologicalloss in weight, which leads to heavy stress on both demandand supply resulting in a steep rise in the price. Scientificallydeveloped storage facilities will help in checking the supplyvolatility and rise in onion prices. Under existing ambientconditions, NHRDF has developed a ventilated conventionalonion storage structure providing proper aeration andventilation without any control on temperature and humidity.This storage structure is popularized in major onion growingstates in India. Recently, the NHRDF has developed animproved storage structure designed to maintain theconstant temperature and relative humidity throughout thestorage period. After six months of storage, highest qualitybulb recovery (21.40 ton), with lowest rotting (0.69%),physiological loss of weight (13.83%) and total loss (14.52%)were recorded in NHRDF improved onion storage structure.Due to highest bulb recovery, highest net returns areobtained. While in NHRDF conventional ventilated storagestructure, moderate quality bulb recovery (16.70 ton),sprouting (2.50%), rotting (10.10%), physiological loss ofweight (20.80%) and total losses (33.40%) were recorded.The lowest quality bulb recovery, highest sprouting, rotting,physiological loss of weight and total loss were recorded infarmer’s storage structure. Apart from these, NHRDFimproved onion storage structure has several advantagesover cold storage structure, conventional ventilated storagestructure and farmer’s storage structure.