They point to the fact Sony does not actually make its own plasma models and is struggling to stay competitive.
Analysts say Sony would be better off sticking to rival technology LCD.
With plasma and LCD competing to be the most popular flat television technology, plasma currently has the advantage in that its screens can be made significantly larger.
The Nihon Keizai Shimbun newspaper said Sony, the world's number two plasma TV maker behind Matsushita, owner of Panasonic, and ahead of third-largest Hitachi, would exit the plasma business as early as the spring of 2005.
Sony responded with a statement that while it would concentrate on LCD screens, it had no plans to pull out of plasma.
Electronics analyst Kazuya Yamamoto said it was difficult for Sony to make a profit out of plasma screens.
"Because Sony relies 100% on others for its panels, it has little room to lower costs," he said.
Sony's overall television division posted a loss of 6.1bn yen ($58.64m: £30.2m) in the three months to 30 September.
Until now, LCD TVs have primarily addressed the 20- to 40-inch screen-size market, while plasma has been used for the 40- to 60-inch range.