|Place of birth||Austria|
|Place of death||United States|
|Playing position||Inside Forward|
|1927–1929||New York Nationals||26||(12)|
|* Senior club appearances and goals counted for the domestic league only.
Siegfried Wortmann (born Austria; died United States) was an early twentieth century Austrian football (soccer) inside forward who played professionally in Austria and the United States. He also earned one cap, scoring a goal, with the Austria national team in 1926.
Wortmann began his career with Hakoah Vienna as a youth player, but began seeing first team time during the 1923-1924 season. In 1924, he became a first team regular as Hakaoh won the 1925 Austrian League title. In 1926, Hakoah toured the United States. Impressed by the high pay and relatively low anti-Semitism compared to the Austrian league, Wortmann and several of his team mates moved to the American Soccer League. In 1927, he signed with the New York Nationals, winning the 1928 National Challenge Cup with the Nationals. Wortmann scored the lone Nationals goal in the 1-1 first game tie with Ben Millers. In the replay, Wortmann again scored as the Nationals easily disposed of the Ben Millers, 3-0. In 1929, he moved to the Hakoah All-Stars, playing four seasons with them. As the ASL began to collapse in 1931, Wortmann returned to Austria to sign with First Vienna FC, winning the 1932-1933 Austrian League title. At some point, he returned to the United States, this time permanently, and joined Brookhattan of the second American Soccer League, playing until his retirement in 1936. After his retirement, he owned a clothing store in the United States.