The invention provides a triangular valve, in particular to a novel triangular valve. The novel triangular valve comprises a valve body, a quick-opening spool, a hand wheel and a threaded cap. An inlet and an outlet are arranged in the valve body and form an angle of 90 degrees. About 1/2 of the quick-opening spool is installed in a valve cavity of the valve body. A chamfer is arranged at a matching position of a valve seat of the valve body with the spool. Main parts of the valve body, the hand wheel, the threaded cap and the quick-opening spool are made of stainless steel. According to the novel triangular valve, the stainless steel is used for manufacturing the triangular valve, and accordingly the service life is increased, the abrasive resistance is improved, used parts are few, and the novel triangular valve has the advantages of being simple to operate, low in cost and small in size.