The Japanese electronics and entertainment giant reported a quarterly loss of ¥24.6 billion (£202m) compared with a ¥15.5 billion loss a year earlier.
Tokyo-based Sony lowered its earnings forecast for the business year through March 2013 to a ¥20 billion profit, down from ¥30 billion projected in May, citing uncertainty in foreign exchange rates and global demand.
The company said it was hurt in the April-June quarter by a strong yen, which eroded overseas earnings, and by declining sales of liquid-crystal display TVs and PlayStation 3 and PS Vita video game consoles.
In its movies division, Sony achieved a 6 per cent increase in sales with the hit Men in Black 3, and better cable and network programme revenue. But it had an operating loss partly because of marketing expenses for other 2012 films, including The Amazing Spider-Man.