Worcester Reed Warner (May 16, 1846 – June 25, 1929) was an American mechanical engineer, entrepreneur, manager, astronomer, and philanthropist.

On the completion of their apprenticeship in 1870, both entered the employ of Pratt & Whitney in Hartford, Connecticut.

The firm, Warner & Swasey, was initially located in Chicago but soon moved to Cleveland.

Warner was a charter member of the American Society of Mechanical Engineers,[1] and from 1897[1] to 1898 he served as the 16th president of ASME.

The Worcester Reed Warner Medal is awarded by the ASME for "outstanding contribution to the permanent literature of engineering".