President Hu Jintao of China is due to meet Cuban leader Raul Castro on the second day of his state visit to Cuba, BBC reported.
Mr Hu has laid a wreath at a monument to the Cuban independence hero, Jose Marti, in Revolution Square in Havana.
China has agreed to continue buying raw nickel and sugar from Cuba and to send food aid to the island, Cuban TV said.
The visit is part of Mr Hu's tour of Latin America, where he is seeking to boost economic ties with China.
It is still unclear whether the Chinese president will meet the ailing former Cuban leader, Fidel Castro, who has not been seen in public since undergoing emergency surgery in 2006.
Cuban state television announced that the two countries had reached dozens of agreements but no value for the deal was quoted.
China is now Cuba's biggest trading partner after Venezuela, with bilateral trade at $2.3bn (£1.5bn) in 2007.
Across Latin America, China has seen its trade climb from $13bn in 2000 to more than $100bn in 2007.
"My visit is aimed at increasing friendship and co-operation between our two nations, and working together with our Cuban comrades to build a promising future," Mr Hu said in a statement.
Throughout the Cold War Cuba was traditionally a much firmer ally of the Soviet Union than China, but that changed when the Soviet Union collapsed in 1991, leaving Cuba almost bankrupt, says the BBC's Michael Voss in Havana.
China offered Cuba soft loans to help it through the difficult 1990s, and these loans are now beginning to come due.
Restructuring their repayment is likely to be one topic on the agenda when the two leaders meet on Tuesday, our correspondent says.
Other agreements set to be signed reportedly include Chinese-backed energy prospecting in Cuba, and other deals in education and health.
Mr Hu arrived in Cuba from Costa Rica, where he signed co-operation agreements.
He will travel on from Cuba to Peru where he will attend the Apec (Asia-Pacific Economic Co-operation) summit in Lima on 21 and 22 November.
But China is not the only power interested in securing greater access to the raw materials and other Latin American resources.
President Hu will be followed next week by Russian President Dmitry Medvedev, whose tour of the region includes a visit to Cuba.
Although both Cuba and China are run by Communist parties, they have pursued very different economic models.
China has adopted market economics while Cuba still has a command system with most of the economy under state control.
When Mr Hu last visited Cuba in 2004 Fidel Castro was still in charge of the country.
His younger brother, Raul Castro, officially took over the presidency in February 2008 and has introduced some reforms.
Raul Castro saw China as a potential model for Cuba to follow, says BBC regional analyst Emilio San Pedro.
China, a modern-day economic powerhouse in a world of financial uncertainty, sees Cuba with its need for investment and political support as an important ally in its long-range plans to strengthen and expand its ties with the rest of Latin America, he adds.