Cosco said the loss was due to excessive shipping capacity as well as the euro debt crisis and sluggish demand in the US.
Its container shipping contributed CNY23.1 billion in first half revenue, but was stymied by the slow recovery of the global economy and the spreading European debt crisis.
"The global demand for container shipping was moderate in the first half of 2012," it said in a filing with the Hong Kong stock exchange.
"The capacity of major routes has increased significantly due to the delivery of new vessels, reduction in idle capacity and the replacement of small vessels by bigger ones," it said.
The company possesses a fleet of 166 containerships at the end of June, a year-on-year 16.8 per cent year on year in terms of total shipping capacity.
The company said it had plans to change its route structure and improve allocation of capacity between traditional and emerging markets, speed up the exploitation of emerging markets and explore potential inland sources of cargo through land and river transport to form an effective global transport network.
But sluggish demand still plagued container shipping during the peak season and the European sovereign debt crisis had led to the weak growth of the global demand for container shipping, the company said.