A local official said most of those who had died were women, children or elderly. The bridge in Morbi had been reopened just a week ago after repairs since 2020.
There was overcrowding on the bridge at the time as people celebrated the Diwali festival, officials said.
The 230m (754ft) bridge on the Machchu river was built during British rule in the 19th Century.
The death toll is expected to rise further.
Police, military and disaster response teams were deployed and the rescue effort is continuing.
More than 177 people have been rescued so far, officials said.
"Many children were enjoying holidays for Diwali and they came here as tourists," told eyewitness.
"All of them fell one on top of another. The bridge collapsed due to overloading."
Videos on social media showed dozens clinging onto the wreckage as emergency teams attempted to rescue them. Some survivors clambered up the bridge's broken netting, and others managed to swim to the river banks.
Reports said several hundred people were on the bridge when it collapsed at around 18:40 India time (13:10 GMT) on Sunday.
A video shot before the collapse showed it packed with people and swaying and many gripping the netting on its sides.
Gujarat is the home state of Indian Prime Minister Narendra Modi, who has announced compensation for the families of victims. He said he was "deeply saddened by the tragedy".
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