China's five leading petrochemical companies posted combined profits of 27.1 billion yuan last month, an increase of 44.8 percent year-on-year, according to the China Petroleum and Chemical Industry Association (CPCIA).

The five companies are China National Petroleum Corp, China Petrochemical Corp, China National Offshore Oil Corp, Sinochem Corp, and Shaanxi Yanchang Petroleum (Group) Co.

In April, revenue for the five companies' main business was 207.7 billion yuan, a decrease of 28 percent year-on-year, said the association.