Tokyo Electric Power Co is likely to book about a 1 trillion yen ($12.3 billion) net loss for its fiscal year that ended in March due to losses from the accident at its Fukushima Daiichi nuclear plant.
That would be highest ever annual loss reported by a Japanese company, excluding financial institutions, the Nikkei business daily said.
The utility's president, Masataka Shimizu, will step down to take responsibility for the handling of Japan's worst ever nuclear accident, the Yomiuri newspaper said. Senior executive Katsutoshi Chikudate will become the firm's new president.
More than two months after a 9.0 magnitude earthquake and a deadly tsunami set off the worst nuclear disaster since Chernobyl.
More than 70,000 people have been forced to evacuate their homes because of health risk and last week the government workers began killing more than a 1,000 cattle which were within the Fukushima no-go zone.
The government has retaliated by declaring a plan to help the Tokyo Electric Power Company (TEPCO) to pay the victims of the crisis with the money they draw from other organizations and taxpayers. The plan has to be approved by parliament as opposition has already showed its dissatisfaction.