Kenya has signed deals worth $5bn (£3bn) with China to build a railway line, an energy project and to improve wildlife protection, officials say.
They were signed during Kenyan President Uhuru Kenyatta's first visit to China since his election in March.
Mr Kenyatta's "vigour" would lead Kenya to "greater accomplishments", China's President Xi Jinping said.
Mr Kenyatta has a strained relationship with the West as he is facing violence-related charges at The Hague.
He is due to go on trial at the International Criminal Court (ICC) later this year for allegedly fuelling violence after disputed elections in 2007, charges he denies.
During Kenya's election campaign, the European Union said it would have limited contact with him if he was elected president.
The US warned Kenyans of "consequences" if he was voted into office.
Mr Kenyatta accused them of meddling in Kenya's internal affairs, and pledged to strengthen ties with the East.
Key rail link
In a statement, his office said the deals with China were a "massive boost" to his government.
"The rail link, particularly, is important in the context of East Africa's shared goal of ensuring quicker movement of peoples, goods and services," it quoted Mr Kenyatta as saying.
It will link the Kenyan border town of Malaba with the port of Mombasa, one of the busiest in Africa.
Mr Xi said China was also exploring other areas of investment, including in agribusiness, irrigation, fertiliser production and purchases, and technology.
"These agreements deepen our practical co-operation. China supports Kenya's quest for industrialisation," he said.
The two presidents also pledged to increase contact between China's ruling party and Kenya's ruling Jubilee coalition.
"They agreed that party-to-party contact was essential to bolster political and economic partnerships," Mr Kenyatta's office said.
The statement did not give details about the energy-related projects that China would spearhead or how it would help improve wildlife protection in Kenya, where criminal gangs often ship elephant tusks and rhino horns to east Asia for use in ornaments and medicines.