Ruggiano, who turns 34 in April, will earn $1.65 million in 2016, plus performance bonuses, per Jeff Wilson of Fox Sports Southwest.
The Dodgers acquired Ruggiano from the Mariners on Aug. 31 and he proceeded to mash for the season's final month. Ruggiano was the Dodgers' second-best hitter in September behind Corey Seager, hitting .291/.350/.618 with four home runs and four doubles in 60 plate appearances.
Ruggiano hit .248/.333/.472 on the season in 57 games overall between Seattle and Los Angeles.
The right-hander hit .333/.388/.667 against left-handed pitching as a Dodger in 2015, and in his career has hit .272/.336/.520 against southpaws, a .368 wOBA and 134 wRC+.
The Dodgers originally drafted Ruggiano in the 25th round in 2004.
He opted for free agency on Nov. 5, after he cleared waivers and the Dodgers sent him outright to Triple-A Oklahoma City.