Adsorption chillers have been receiving considerable attentions as they are energy-saving and environmentally benign systems. In order to evaluate adsorption rates, experiments were performed in the batch type adsorption apparatus. Three types of silica gels were investigated under an assortment of experimental conditions that are representatives of the actual operating environments in the adsorber of adsorption chillers. Experimental results revealed the effects of silica gel particle size, bed temperature, and fin pitch of fin tube on the adsorption rate. The $0.25~1.18mm$ particle size of silica gel with high adsorption rate was selected as a suitable adsorbent. The measured adsorption rate became bigger with decreasing particle size. From the comparison of adsorption rate, it is found that the fin tube has about $21\%$ higher value than that of the bare tube. The effect of heat and mass flux is found to be more significant in the fin tube than in the bare tube.