TOKYO—Sony Corp. said this fiscal year is shaping up to be profitable across all its main businesses, marking what executives see as the successful end of a turnaround plan.

Sony struggled for years to pare back unprofitable businesses, often earning low profits when weakness in businesses such as smartphones canceled out strengths elsewhere. But for the current fiscal year ending March 2018, it expects to post an operating profit of ¥500 billion ($4.5 billion) with all business units contributing, said Chief Financial Officer...