Toshihiro Nikai (二階俊博, b. February 17, 1939) is a Japanese politician currently serving as Minister of Economy, Trade and Industry.
Nikai was born in Wakayama Prefecture and attended Chuo University, graduating with a law degree in 1951. He initially worked as secretary for Saburo Endo, a Diet member from Shizuoka. After Endo's death, Nikai returned to Wakayama, where he won a seat on the prefectural assembly in 1975. He was elected to the House of Representatives in 1983.
He was a member of Noboru Takeshita's faction within the Liberal Democratic Party, but left the party in 1993 to join the Shinsei Party. As a member of the Shinseito, he served as Vice-Minister of Transportation under Morihiro Hosokawa. He was later a member of the Liberal Party, Conservative Party, and New Conservative Party. After the NCP merged with the LDP in 2003, Nikai became an LDP member again, and was appointed Director of the General Affairs Bureau in 2004.
In 2005, Prime Minister Junichiro Koizumi tapped Nikai to head the Diet committee in charge of the privatization of Japan Post. Following the general elections of that year, on October 31, Koizumi selected Nikai to head the Ministry of Economy, Trade and Industry, traditionally one of the most highly valued cabinet portfolios.