Ronald Eustace Psmith is a character in several of the comic novels of P. G. Wodehouse. The P in his surname is silent, and was added by himself as he considers himself (with some justice) to be too remarkable to be a mere "Smith".

He is something of a dandy, and has a remarkable ability to pass through the most amazing adventures unruffled (at least until his final appearance).

He appears in four novels: Mike (1909) (the second half of which was also published separately as Mike and Psmith), Psmith in the City (1910), Psmith Journalist (1915); Leave it to Psmith (1923).

Leave it to Psmith differs somewhat in style from its predecessors, in that in it things happen to Psmith (whereas previously it had been more the case that he was a thing that happened to other people).

In his first appearance (in Mike or Mike and Psmith, depending which edition you have) he inexplicably implies to Mike that his first name is Rupert.