Abstract: At present，the static sedimentation method was often applied in solution desilication in the industry of extraction of vanadium from stone coal，namely，allow silaceous vanadium solution to stand for a long time under weak alkaline condition，and then remove the silica gel through filtration after silicon ions agglomerate naturally.The objections to this method are its low desilicating efficiency，long standing time and difficult to filtrate fine silica gel，which lead to over-standard of silicon content in vanadium products.In allusion to the present industrial situation，flocculation method was proposed to remove silicon.The desilicating mechanism was discussed and the variety of desilicating agent as well as the influences of the dosage of desilicating agent，pH value of solution and standing time on desilicating effect were studied.Results indicated that under the weak alkaline condition，desilicating agent A would have a good effect on the desilication process of silaceous vanadium solution and desilicating rate could reach above 90%.Moreover，there is little vanadium loss due to the precipitation during the desilicating process.