Kumar Udaybhansinhji Bahadur was born on 6th Oct 1910 in Shirnagar taluka, district Porbandar in Gujarat. He was last Prince of Jethwa dynasty of Princely state of Porbandar of Gujarat. Rana Saghji Jethwa was 106th ruler and first Rana of Jethwa dynasty during 1120 – 1150. He established the state in 1193 which was later named as Porbandar in 1785. Rana Sahib Natwarsinhji Bhavsinghji Jethwa was coroneted as 180th ruler of Jethwa dynasty. He had no male issue who can futher the linage of dynasty so he adopted Kumar Sri Udaybhansinhji Bahadur who happen to be first son of his cousin Shivsinhji Motiji Jethwa and thus Kumar Udaybhansinhji Bahadur became Prince Udaybhansinhji Natwarsinhji Jethwa and heir apparent to throne of Porbandar on 12 June 1941. He pursued his Bachelor of Agriculture from Government Agriculture College, Poona in 1932.

Prince Udaybhansinhji Natwarsinhji Jethwa established Saurashtra State Central Co-operative Land Mortgage Bank Ltd.in the year of 1951 in the erstwhile state of Saurashtra as an apex body for providing long term agricultural loans to farmers. The changed name is now "The Gujarat State Co-operative Agriculture and Rural Development Bank Ltd." He remained founder and life time chairman of the bank from Sep 1951 to Jul 1973.

Indian Farmers Fertiliser Cooperative Limited (IFFCO) was conceived and registered on 3 November 1967, with the primary objective of production and distribution of fertilisers. Prince Udaybhansinhji Natwarsinhji Jethwa served as founder chairman of IFFCO during 1968 – 1973.

He was chairman of Expert Committee on Multi State Cooperative Society Legislation 1971 set up by Ministry of Agriculture to recommend the scope of comprehensive central legislation and basis on which the same would be framed.

He was selected as member of NCDC Functional committee on Co-operative Agricultural Credit, 1966 and Reserve Bank of India Committee on Co-operative Land Development Banks.

He was awarded “Padma Shri” India’s fourth highest civilian award by Government of India in year 1971, in field of Trade & Industry from the State of Gujarat as a recognition to his contribution in this field, especially for his contributions related to cooperative movement, agriculture trade and industry.

He was also elected president of National Cooperative Union of India during Dec 1967 to April 1971. He was first from the Gujarat to lead the cooperative movement at national level.

He died in Rajkot in Gujarat in 1977.