To elucidate the water-holding mechanism of agar-gel, consolidation and absorption characteristics were investigated. Soilconsolidometer was found to be available for evaluating the consolidation characteristics of agar-gel when the gel was not of too low concentration. On 2% gel, extent of dehydration increased, and water-permeability decreased remarkably by increasing the compression of the gel to 0.071kg/cmcm², while they showed almost constant values at the compression of more than 0.3kg/cmcm². Dehydration by compression increased and water recovery of consolidated gel decreased when 5×10^-3% organic acids were added. Similar trend of results were observed also on addition of 10-1-10^-4% sodium hydroxide. Alcohol reduced water recovery significantly. Water recovery of dried gel decreased linearly by increase in the extent of dehydration. The recovery value for dried gel was lower than that of compressed gel. Developement of a more suitable equipment to measure the consolidation of agar-gel was considered to be necessary for further study.