Bajna is located at . It has an average elevation of 183 metres (600 feet).
India census, Bajna had a population of 12034. Males constitute 54% of the population and females 46%. Bajna has an average literacy rate of 58%, lower than the national average of 59.5%; with 65% of the males and 35% of females literate. 18% of the population is under 6 years of age.