One legislator was hospitalized after the brawl with a head injury.
Ukraine is deeply divided into the Russian-speaking east and south, which favor close ties with Moscow. The western part of the country speaks Ukrainian.
Russian-speakers make up more than 10 percent of the population.
Opponents of the bill say it will stem the development of the Ukrainian language, by creating no incentive for millions of Ukrainians to learn and use it.
Pro-government lawmakers, who draw their support from the Russian-speaking south and east of Ukraine, say it will allow people living there to use the language of their preferences.
On Friday, deputies opposed to the bill blocked the Parliament speaker's podium, preventing the session from starting, while some 200 demonstrators held a noisy protest against the bill outside the building.
The Associated Press contributed to this report.