William Henry Wahl (14 December 1848 in Philadelphia – 23 March 1909) was a United States scientific editor and journalist.

During a trip home from Heidelberg, he made the acquaintance of Henry Morton, resident secretary of the Franklin Institute, who had engaged him for editorial services.

Their proceedings largely supplemented those of the Institute in general and enriched the Journal with many records of original scientific research.

These published investigations anticipated by several years the subsequent commercial development of the art, and were increasingly utilized in the steel making industry where low carbon ferro alloys were required.

He provided that his entire estate (estimated at $75,000) be held in trust for use and benefit of his widow during her life, and that thereafter it be held for the use and benefit of the Franklin Institute, as a memorial to his father, John H. Wahl, provided that within three years after its reversion, an equal sum be contributed from other sources, not including bequests.