But it said it booked gains on its shares in DoorDash, an online food-ordering service based in San Francisco.
SoftBank said the recent crackdown in China on the technology sector weighed on Chinese share prices.
SoftBank’s Vision Fund was hit by a 1 trillion yen ($9 billion) loss in the July-September quarter, according to its chief executive, Masayoshi Son.
Son, who founded the company, acknowledged the latest losses were a big contrast to the booming results it reported for the previous fiscal year.
“We have headed straight into a blizzard in the middle of the winter,” Son told reporters, adding he won’t make excuses.
He said one big factor was a sharp drop in the share price of Chinese e-commerce company Alibaba, in which SoftBank is a shareholder.
But he stressed SoftBank’s main business was shifting to the Vision Fund and becoming less dependent on Alibaba’s performance. However, Vision Fund’s Chinese investments also suffered.
Son said Vision Fund’s investments overall were gaining value. Its portfolio has been constantly changing. It once owned U.S. mobile company Sprint, but Sprint has merged with T-Mobile, in which SoftBank remains an investor.