On Sunday he visited the Longbridge MG car plant, where he faced a small human rights protest.
Downing Street said there was potential to create more jobs and investment opportunities for British businesses.
The two leaders are expected to sign an agreement to help UK companies work with China's regional cities, in architecture, civil engineering and research and development.
British poultry farmers are being allowed to export to China and the visit is expected to see agreements reached for the supply of pigs.
Chancellor George Osborne and Foreign Secretary William Hague are due to join Mr Cameron for the talks and Mr Wen is accompanied by other senior members of the Chinese government.
A Downing Street spokeswoman said: "China's rapid economic rise is good news for the UK. It means more money flowing into our economies and has the potential to create more jobs and investment opportunities for British business at home and in China.
"The summit will be an opportunity to tap that potential and to continue to work closely with China to find global solutions to a range of issues from climate change to global security."
It follows Mr Wen's visit to Longbridge and to Stratford the Chinese premier is a lifelong fan of William Shakespeare.
