Johnson Siding is an unincorporated community in Pennington County, South Dakota, United States.

It is the only significant business district in the Rimrock Area, with a gas station/general store, deli, casino, tavern, the Johnson Siding Volunteer Fire Department firehouse, the Rimrock Evangelical Free Church meetinghouse, and a community center.

[citation needed] Johnson Siding is named for a siding on the old Rapid City, Black Hills and Western Railroad (the Crouch Line) which ran up Rapid Creek between Rapid City and the Black Hills Highline at Mystic, which was originally constructed to serve the Johnson Sawmill, located a short distance upstream from the existing town.

Johnson Siding was the site of the political convention which first organized the South Dakota Libertarian Party in 1992, at which Costas "Gus" Hercules was nominated to the U.S.

[citation needed] Johnson's Mill was also the head of the Hisega Flume, a wooden waterway constructed high on the south cliffs of the Rapid Creek canyon to supply a small hydroelectric plant at Big Bend near present-day Thunderhead Falls in the early 1900s, one of several National Engineering Landmarks in the Black Hills.