Gopalganj is a city and a municipality in and the headquarters of Gopalganj district in the Indian state of Bihar.
Gopalganj is located at 26°28’N 84°26’E26.47°N 84.43°EIt has an average elevation of 66 metres (216 feet).
As of 2001 India censusGopalganj had a population of 54,418. Males constitute 53% of the population and females 47%. Gopalganj has an average literacy rate of 63%, higher than the national average of 59.5%: male literacy is 70%, and female literacy is 55%. In Gopalganj, 15% of the population is under 6 years of age.