由中国数学会奥林匹克委员会主办、宁夏数学会和长庆银川高级中学承办的第四届中国西部数学奥林匹克于2004年9月25日至30日在宁夏银川举行. 有西部11个省、市、区派出代表队参加了这次活动,他们是:西藏、贵州、内蒙、广西、宁夏、重庆、四川、陕西、青海、甘肃和新疆;周边的省份山西、海南、江西、河北以及香港特区派代表队参加了比赛;友好邻邦哈萨克斯坦也派代表队参赛.共有21支代表队,每支代表队包括领队一名,高三以下的学生四名. The Fourth Western Mathematics Olympiad hosted by the Chinese Mathematical Society Olympic Committee, the Ningxia Mathematical Society and the Changqing Yinchuan Senior High School was held in Yinchuan, Ningxia from September 25 to 30, 2004. There are 11 provinces, cities and districts in the west. Representative teams were sent to participate in the event. They were: Tibet, Guizhou, Inner Mongolia, Guangxi, Ningxia, Chongqing, Sichuan, Shaanxi, Qinghai, Gansu, and Xinjiang; neighboring provinces Shanxi, Hainan, Jiangxi, Hebei, and Hong Kong SAR sent teams. Participated in the competition; Kazakhstan, a friendly neighbor, also sent teams to participate in the competition. There are 21 teams representing each team, including one in the team leader and four in the third year.