Rathorji (Udaibhanotji) Abhai Kanwarji d.of Raja Akhai Singh of Bandanwara in Ajmer Sawai Prithvi Singh II (9 January 1762 – 13 April 1778), also known as Prithviraj Singh II, was the Kachwaha Rajput ruler of the Kingdom of Jaipur from 5 March 1768 until his death on 13 April 1778.

Being elder, Prithvi Singh succeeded his father on the throne and his mother queen Chundawatji became the regent.

One of his nobles, Raja Pratap Singh of the Naruka Kachwahabranch of nobility separated himself from the State of Jaipur and established an independent kingdom at Machheri near Alwar and laid the foundation in 1770 which remained an independent ruling territory and later came to known as Alwar State.

Sawai Prithvi Singh II ruled for 10 years and died of a fall from his horse in 1778 at the age of 15, leaving behind one widow his third queen the Kishangarh princess who being pregnant was sent to his father's protection giving birth to her late husband's only son Man Singh the undisputed heir to the throne of Jaipur.

"Vanshavali" Genealogy of the rulers of Amber & Jaipur by "Harnath Singh Dundlod" Genealogy Records of Raoji Ram Singh (Borada) Sarwad Ajmer,Rajasthan contact no.9928515865 This biography of a member of an Indian royal house is a stub.