The visit comes follows an announcement last week that Cambodia will expand consular services to six cities in China.
All three companies are owned by Ly Yong Phat, a powerful senator for the ruling Cambodian People’s Party.
The 10-nation bloc of countries has become one of the fastest-growing regions in the world.
CIMB said in a statement it will operate a 100-percent owned subsidiary with headquarters in Phnom Penh.
Phnom Penh Sugar is owned by Ly Yong Phat, a powerful senator for the Cambodian People’s Party.
The delegation included three Khmer monks who had spent about one year in jail each in Vietnam.
The agreement, which is expected to spur trade, tourism and other activities in Cambodia.
China has pledged to provide military aid, including more than 250 trucks, exceeding a previous aid scrapped by the US.
The land dispute in Kampong Speu underscores the difficulties arising throughout Cambodia.
Un Sokhom was the editor in chief of the Neak Prayuth newspaper until he fled to the US in 2004 in fear of his safety.
Organizers of the Cambodian Confederation of Unions had planned to show the film, which questions the motives behind the 2004 murder.
Cambodia has sought similar deals in Middle Eastern countries like Kuwait and Qatar, where food shortages are a concern.