Several Taiwanese lawmakers exchanged punches and threw cups and bottles of water at each other on Friday.
The parliament is set to vote on whether to hold a referendum on completing construction of the plant, which is located close to Taipei.
Nuclear power is controversial in Taiwan, where safety fears remain in the wake of Japan’s Fukushima disaster.
The nuclear plant, also known as Nuke 4, would be the island’s fourth. It has been in construction for more than 10 years, and is near completion.
However, Taiwan’s opposition Democratic Progressive Party is against the plant, citing safety fears.
More than 200,000 people took part in anti-nuclear protests in March.
The government says the $9bn (£6bn) facility is needed to prevent a power shortage.
Taiwan frequently experiences earthquakes. A 6.1 magnitude earthquake struck central Taiwan in March, injuring at least 20 people.
In March 2011, an earthquake and tsunami damaged Japan’s Fukushima Daiichi nuclear plant, triggering a meltdown.
Experts say years of work lie ahead before the problems at the plant can be fully contained.
Taiwan’s parliament has experienced brawls in the past. In June, lawmakers clashed over capital gains tax