Garlic has been used not only as a spice and a flavoring agent for food but also as a supplement for medicinal effects, such as antimicrobial, antithrombotic, antioxidant and anticancer activities. The medicinal properties of garlic are attributed to allicin and its degradation products. Allicin is not present in intact garlic. It is rapidly generated when raw garlic is crushed or chopped. The enzyme allinase comes into contact with alliin and converts alliin into allicin and pyruvic acid. However, allicin was not found in the blood after consumption because allicin changed into diallyl disulfide. Diallyl disulfide exhibits ability to lower cholesterol and blood lipid levels. The objectives of this work were therefore to develop a novel drying method which can produce garlic powder with higher content of diallyl disulfide by drying chopped garlic using heat pump and combined far infrared radiation (FIR) and heat pump drying, comparing with hot air drying. The effects of sample preparation, drying method, drying temperature and intensity of FIR on the drying characteristics and the qualities of the dried chopped garlic in terms of allicin content, diallyl disulfide content, volatile oil content and color were subsequently evaluated. The fresh garlic was prepared in 2 types; the first type of the preparation is done by chopping into approximately 2 mm3 and then drying, and another type by chopping into the same size -ivand keeping at 25oC for 3 hours before drying. Hot air drying was performed at temperatures of 50, 60 and 70°C whereas heat pump drying was performed only at a temperature of 50°C. The radiation intensities for combined FIR and heat pump drying were 250, 350 and 450 W. A superficial air velocity used in this study was 0.5 m/s. The experimental results showed that drying at higher temperatures and higher FIR intensities took shorter time than that at lower temperatures and lower FIR intensities. In addition, the diallyl disulfide content had an increasing trend while the allicin content had a decreasing trend when drying temperature and FIR intensity increased. However, their color was browner as manifested by the lower L-value and the higher a- and b-values. Moreover, garlic powder prepared by keeping at 25o C for 3 hours before drying had higher diallyl disulfide content but their color was darker as compared with the non-keeping samples.