Kaneko served as Minister of Agriculture, Forestry and Fisheries from October 2021 to August 2022.

Kaneko first entered public office as a member of the Nagasaki Prefectural Assembly in 1975.

He resigned during his third term in the assembly in 1983 to contest the national House of Representatives seat that was held at that time by his father Iwazō Kaneko.

Iwazō died at the age of 79 on 27 December 1983, 9 days after his son's election victory.

He chose not to seek a fourth term and publicly endorsed his deputy Hōdō Nakamura at the February 2010 gubernatorial election .