UPDATE 1-SoftBank Group Q2 operating profit rises 21 pct on Vision Fund boost

* Q2 operating profit rises to 395.6 bln yen from 328.1 bln yr ago

* Operating profit buoyed by Vision Fund gains (Adds details on Vision Fund)

TOKYO, Nov 6 (Reuters) - Japan's SoftBank Group Corp reported on Monday a 21 percent rise in second-quarter operating profit as the value of its technology investments grew.

The Japanese tech and telecoms firm is funnelling money to U.S. firms as it invests in technology companies around the world, including through its $98 billion Vision Fund, as founder Masayoshi Son pursues his vision of a future driven by artificial intelligence, interconnected devices and robotics.

Profit for the July-September quarter rose to 395.6 billion yen ($3.46 billion) from 328.1 billion yen a year earlier, the company said. Excluding profit from the Vision Fund, income would have fallen 4 percent.

Son is under pressure to turn around its U.S. wireless unit Sprint Corp, especially after it broke off merger talks with T-Mobile US Inc.

SoftBank said on Sunday it would raise its stake in Sprint to under 85 percent from 83 percent in a show of commitment to the No. 4 U.S. wireless carrier which, while managing to grow its customer base, has relied on heavy discounting to do so and is weighed down with $38 billion of debt. ($1 = 114.2700 yen) (Reporting by Sam Nussey; Editing by Muralikumar Anantharaman)