The purpose of this study was to test the performance of dowel joints in improved woods, and to research the suitable design of joints, for developing suitable materials for furniture industry. According to the experimental results: in jointing strength of improved woods, compreg wood was the most efficiency but W.P.C. was the worst. Both of compreg wood and W.P.C. were difficult in machining, only staypak was the best in machining and jointing strength. So the most suitable materials for furniture was staypak. In respect of adhesives, powdered UF adhesive was the most suitable for the jointing of improved woods. The idealist glue-spreading method was the glue spreaded on the inside of dowel hole and matching surface. Regarding the spacing and withdrawal strength, they showed lower relationship, but it was greatly related to the static bending strength.