Robert Paterson Rithet (April 22, 1844 – March 19, 1919) was a Scottish-born businessman and political figure in British Columbia, Canada.
He was born in Cleuchhead near Applegarth in Dumfriesshire, the son of John Rithet, a farmer, and Agnes Paterson, and was educated at Annan.
In 1862, Rithet came to Victoria where he prospected for gold and helped build roads in the Cariboo district.
In 1870, he moved to J. Robertson Stewart's company; with the help of Andrew Welch, he took over the operation of the business the following year.
Rithet served as a justice of the peace and was involved in salmon canning and steamship lines.