The present invention provides a high-strength wear-resistant steel plate with Brinell hardness of ≧HB420, comprising the following chemical compositions (by weight %) C: 0.205-0.25%, Si: 0.20-1.00%, Mn: 1.0-1.5%, P≦0.015%, S≦0.010%, Al: 0.02-0.04%, Ti: 0.01-0.03%, N≦0.006%, Ca≦0.005%, and at least one of Cr≦0.70%, Ni≦0.50%, Mo≦0.30%, other compositions being Ferrum and unavoidable impurities. Also provided is a method of manufacturing the wear-resistant steel plate has remarkable TRIP effect in use, improving substantially its wear resistance, thereby meeting the high demand for wear-resistant steel plates in related industries.