Kargahar is a village and corresponding community development block in Rohtas district of Bihar, India.

The sex ratio of the block in 2011 was 908 females to every 1000 males, which was the lowest among rural areas in Rohtas.

[2] A majority of Kargahar block's workforce was engaged in agriculture in 2011, with 31.77% of workers being cultivators who owned or leased their own land and a further 44.45% being agricultural labourers who worked another person's land for wages.

[2] Of the 198 inhabited villages in Kargahar block, 143 have schools and 10 have medical facilities.

Kargahar village also has a public library, a community centre with sports fields, a regular mandi, and a weekly haat.