Jacob Jung, Jr. (January 11, 1857 – May 3, 1931) was an American businessman and politician from Sheboygan, Wisconsin.
He learned the carriage- and wagonmakers trade, and worked fourteen years at it before buying out his father's business, the Jung Carriage Company, and running it until 1917.
In 1888 he also went into the mercantile business and founded the J. and W. Jung Company department store, which he ran with two of his sons.
In 1922, he was elected to represent the 1st Sheboygan County district of the Wisconsin State Assembly (the City of Sheboygan) as a Republican, with 3,747 votes to 2,173 votes for Socialist Ernest Kreuter (the incumbent, Republican William G. Kaufmann, was not a candidate).
Jung died at his home in Sheboygan, Wisconsin after being ill for a few months, leaving behind his widow and five children.