Stella Hackel Sims (born 1926) was Director of the United States Mint from 1977 to 1981.

Stella Bloomberg was born in 1926 in Burlington, Vermont. She was educated at the University of Vermont, graduating in 1945, and at the Boston University School of Law, receiving her J.D. in 1948.

In 1949 she married Donald H. Hackel (1925--1985). In 1956 she was elected prosecutor of Rutland, Vermont, holding that office until 1963. From 1963 to 1973, she was Commissioner of the Vermont Department of Employment Security. In 1971-72, she was also President of the Interstate Conference of Employment Security Agencies. She was elected Vermont State Treasurer in 1974 and served one term, 1975 to 1977. She ran unsuccessfully for Governor of Vermont in 1976. She then returned to Rutland as city attorney.

In 1977, President of the United States Jimmy Carter named Hackel Director of the United States Mint, and she subsequently held this office from November 1977 to April 1981. In that capacity, she oversaw the creation of the Susan B. Anthony dollar in 1979. During her time at the Mint she remarried and became known as Stella Hackel Sims.