He said China is expecting the summit to send positive messages of unity, cooperation and double win to the international community.
It is the first time that the BRICS summit is held on the African continent, with the cooperation between the BRICS countries and Africa high on the agenda.
Xi said both China and Africa are of the developing world and share broad common interests, pledging Beijing will continue its role as a staunch supporter of Africa's development.
"No matter how international landscape may change, China will continue to support and promote Africa's efforts to achieve peace, stability, prosperity and development, seek strength through unity and participate in international affairs on a basis of equality," the president said.
China and Africa are enjoying all-around and mutually beneficial cooperation, he added.
In addition to attending the BRICS summit, Xi is also due to visit Russia, Tanzania, South Africa and the Republic of Congo between March 22 and 30 on his first overseas tour since he took office last week, according to the Chinese Foreign Ministry.
With Russia to be the first leg, Xi said his forthcoming visit to Moscow shows the high level and special nature of the comprehensive strategic partnership of coordination between the two countries.
"The fact that I will visit Russia, our friendly neighbor, shortly after I become China's president, is a testimony to the great importance China places on its relations with Russia," Xi said.
"China and Russia are each other's major and most important strategic partners of coordination and both countries accord priority to their bilateral relationship in their overall diplomatic agenda and foreign policy," Xi said.
Seeking a dream wedding at Beijing Wedding Expo