"We cannot tolerate unethical conduct anywhere," said Mark Dybul, head of the Global Fund, which is backed by governments and private donors such as Microsoft founder Bill Gates.
"Although this case had no direct impact on Cambodia's fight against malaria, taking commissions in exchange for contracts violates our mission of public service. We remain fully committed to pursuing fraud and taking action when we find it."
The move followed a probe by Global Fund inspectors into claims of corruption at the suppliers, Swiss-based Vestergaard Frandsen and the Singapore unit of Japanese firm Sumitomo Chemical.
The investigation found that between 2006 and 2011, staff from the two companies paid a total of $410,000 (305,000 euros) to two Cambodian officials in return for awarding contracts for insecticide-treated bed nets that help prevent the spread of malaria.
Vestergaard and Sumitomo both fully cooperated with the probe and have taken action against the staff involved, the Global Fund said.
The probe found that while a Global Fund grant in Cambodia was compromised by the payments, all the mosquito nets procured by that grant were provided as intended.
In total the Global Fund has spent $331 million since 2003 on programmes in Cambodia to fight AIDS, tuberculosis and malaria.
Over that period Cambodia has seen an 80-percent decline in malaria deaths, a 45-percent fall in tuberculosis cases and a 50-percent drop in HIV numbers, the Fund said.