Despite Alfred Hitchcock’s many affinities with Film Noir—he made The Lodger, one of the earliest Film Noirs, and Vertigo, the very best of Film Noir, as well as a dozen or more films that come under the large Film Noir umbrella—he created his own genre which differs from Film Noir in several ways.
First, his films are not set in a dark underworld milieu. Hitchcock preferred a seemingly normal upper middle class or gentrified setting. Second, Hitchcock seldom resorted to the Film Noir chiarascuro visual style. Suspense in Hitchcock takes place in the daylight. And finally, Hitchcock very often combines crime with a genuinely romantic love story, Rear Window being a good example.
As stated above, Hitchcock created a genre of his own.