The 9 billion dollar deal would allow Panasonic, which makes Viera TVs and Diga Blu-ray disc players, to take advantage of struggling Sanyo's green businesses in solar panels and rechargeable batteries.
Sanyo shares dropped 3.6 percent while Panasonic shares gained 2.9 percent after trading ended in Tokyo.
Sanyo was founded by a brother-in-law of Panasonics founder.