The Japanese automaker said net income is expected to fall 54 percent to $2.3 billion in the 2012 fiscal year ending in March, The New York Times reported.
Global sales likely will fall to 7.38 million vehicles, down from a projected 7.6 million, Toyota said in a statement.
The revised sales estimates likely will plunk Toyota behind General Motors Co., which sold 7.48 million vehicles in 2010, analysts told the Times.
The lower profit projection could push rivals ahead of Toyota, the Times said. Nissan forecasts a 290 billion yen ($3.7 billion) net profit this year. Analysts said South Korean automaker Hyundai's earnings could top $6 billion this year.
Toyota was hard hit by Thailand's worst flooding in decades. The floods killed more than 600 people, damaged millions of homes and overwhelmed hundreds of factories. The flooding disrupted Toyota production in plants as far away as the United States, causing a net shortfall of 230,000 vehicles, the automaker said, adding that waters were receding and most regions are back to normal output.
Japan's catastrophic earthquake and tsunami in March cut supply chains and forced Toyota to suspend or scale back production in plants in Japan and overseas.