To prevent damage, corruption, and maintain the quality of fruits, vegetables and food their long-term protection is essential. There are several methods for preserving foods including canning, freezing and drying. Among these methods, drying, is an effective and practical method for reducing post-harvest food losses, especially for developing countries that have poor facilities for low temperature processes. Traditional sun drying has been used for a long time. Nowadays, in order to increase the quality of dried materials, solar dryers are used. In this study, a solar dryer based on double-pass solar air heaters was designed and developed. For designing the dryer, simplicity, efficiency and economic aspects were considered. The device consisted of three axial flow fans in upper pass channel, chassis and body and finned collector. Despite of using inclined collectors in further solar dryers, in this study, horizontal design (angle 0°) was used for the collector. Investigations revealed that in addition to benefits of designing for this pattern, it received adequate energy in warm months which drying of products is commonly done. The measuring systems included an on-line weighing system, a temperature measuring system at different parts of the dryer and solar radiation intensity meter. To improve the performance of the solar dryer, paraffin as the phase change material (PCM) was used. Surveying the drying performance showed overall efficiency of 24.6%, 29.8% and 31.2 % at different flow rates of 0.044, 0.0359 and 0.0269 kg s -1 , respectively. Applying energy storage system, led to 4.3 °C increase in the inlet air temperature into the product's tray. Product moisture content at the end of the first day reached to 35% (dry basis) and 41% (dry basis) with energy storage system and without it, respectively. The moisture content in the solar dryer decreased to 23.9% (dry basis) after 7 h, while in the traditional sun drying it reached to 23% (dry basis) after 30 h. For modeling drying kinetics eight different empirical models were investigated and the k-square and root mean square error regarding the experimental data and predicted ones by the model were calculated to evaluate them. The most appropriate model to describe drying kinetics of garlic slices was the logarithmic model under the forced flow in solar. The quality of the dried product was assessed interms of shrinkage, absorption and color indices under solar drying, traditional sun drying and oven methods. Color indices showed that product browning was more in traditional method than the other methods. Effect of different drying methods on product shrinkage was not significant. Despite the significant effect of drying method on the water reabsorption, the values were close to each other. Economic evaluation of the developed solar dryer showed a suitable performance for the drying of garlic considering Iran geographical position. Payback time of 0.89 year and total cost of 150 US$ were calculated for the developed solar dryer. Key words: Solar dryer, quality, drying performance, garlic