Temple De Hirsch Sinai is a Reform Jewish congregation with synagogues at campuses in Seattle and nearby Bellevue, Washington, in the United States.

[2] The old Temple De Hirsch building (or Old Sanctuary) was listed on the National Register of Historic Places, but was demolished in 1993.

[2][6] Construction on the new Temple De Hirsch designed by Seattle-based architect Julian F. Everett was begun in 1907, completed in 1908, and dedicated on the congregation's ninth anniversary, May 29, 1908.

In 1909, Koch established a newsletter, Temple Tidings, initially a weekly and later a monthly (currently bi-monthly) publication.

Levine was a devoted ecumenicist, co-hosting a television program called Challenge with a Catholic priest and a Protestant minister.

Samuel E. Goldfarb, co-composer of the Hanukkah song "I Have a Little Dreidel" was music director of Temple De Hirsch from 1930 to 1968.

[10] The Temple De Hirsch Sinai Libraries were founded in 1908 and continue to provide a wealth of information for the congregation and community.

In both Seattle and Bellevue sites, the system contains over 10,000 books, periodicals and CDs, with a specialty in materials on Judaism, history, culture, holiday and the Holocaust.