BlackBerry plans to fire up to 40% of its work force, or the equivalent of about 5,000 employees, according to The Wall Street Journal.
The layoffs will happen by the end of the year.
BlackBerry has largely failed to gain traction for its new mobile operating system called BlackBerry 10 and the flagship phones it runs on, the BlackBerry z10 and BlackBerry Q10. In its last earnings report, BlackBerry said it lost $US84 million and only sold 2.7 million BlackBerry 10 devices.
The company has also abandoned its PlayBook tablet business.
BlackBerry will report earnings for last quarter next week.