Arjunpur is a village in Kishni block of Mainpuri district in Uttar Pradesh, India..
In 2011, Arjunpur had a population of 2,334 in 394 households. This population was 53.4% male (1,246) and 46.6% female (1,088). The 0-6 age group numbered 449 (240 male and 209 female), or 19.2% of the total population. 1,157 residents were members of Scheduled Castes, or 49.6% of the total.
The 1981 census recorded Arjunpur as having a population of 958 in 173 households.
The 1961 census recorded Arjunpur as comprising four hamlets, with a total population of 844 (484 male and 360 female) in 154 households and 125 physical houses. The area of the village was given as .
In 2011, Arjunpur had one primary school. It did not have any healthcare facilities. Drinking water was provided by hand pump and there were no public toilets. The village had a post office and public library, as well as at least some access to electricity for all purposes. Streets were made of kachcha materials.