The League was organized in 1922 as The Junior Welfare League of Bethlehem, Pennsylvania. The Association of Junior Leagues International (AJLI), then AJLA, incorporated the Junior League of the Lehigh Valley during their 1943-44 League year. It is one of 293 Junior Leagues representing over 171,000 women in the United States, Canada, Mexico, and England.

In 2023, the Junior League of the Lehigh Valley will celebrate 80 years of service to communities in the Lehigh Valley.