Sunil Kumar, who had been accused of raping a minor girl was arrested on May 7 last and was transferred to Dausa jail from Bandikui on May 13 on the directions of the court, police said.
Sadar police station in-charge Muninder Singh Chaudhari told that Sunil committed suicide by hanging himself with a towel in jail's bathroom.
"An FIR has been registered in this connection after jail authorities submitted a report," Chaudhari said.
Sunil's family in Haryana's Hisar has been informed and post-mortem would be carried out only after they reach Dausa, he said.