Toshiba Corp posted 37.46 billion yen ($456.3 million) in operating profit for October-December, compared with 14.49 billion yen in the same period the previous year, on healthy sales of NAND flash memory used in smartphones and tablet computers.
That compares with a mean forecast of 50.2 billion yen ($605.7 million) in a survey of 5 analysts by Thomson Reuters I/B/E/S.
The company left its full-year operating profit forecast unchanged at 250 billion yen, compared with an average estimate of 269.9 billion yen based on 22 analysts polled by Thomson Reuters I/B/E/S.
Toshiba is the world's second largest supplier of NAND chips after South Korea's Samsung Electronics and competes with Hewlett-Packard and Dell in personal computers.
Toshiba shares closed down 3.2 percent ahead of the earnings announcement, compared with a 1.2 percent dip in the Nikkei stock average.
(Reporting by Isabel Reynolds; Editing by Dhara Ranasinghe)