I have blog posts on the following of his films:
Osaka Elegy (1936)
Sisters of the Gion (1936)
The Life of Oharu (1952)
Ugetsu (1953) at the bottom of this post
FilmRef.com has descriptions of his films. Bright Lights Film Journal has an article on him, describing him as:
with Ozu and Kurosawa one of the three undisputed masters from the golden age of Japanese cinema
Senses of Cinema (they have another article here) profiles him, saying
If he is, as I believe, the greatest of Japanese directors, then he has eluded general recognition as such only through unpropitious circumstances.
FilmReference.com opens their article saying,
By any standard Kenji Mizoguchi must be considered among the world's greatest directors. Known in the West for the final half-dozen films which crowned his career, Mizoguchi considered himself a popular as well as a serious artist. He made eighty-five films during his career, evidence of that popularity. Like John Ford, Mizoguchi is one of the few directorial geniuses to play a key role in a major film industry. In fact, Mizoguchi once headed the vast union governing all production personnel in Japan, and was awarded more than once the industry's most coveted citations. But it is as a meticulous, passionate artist that Mizoguchi will be remembered.and closes by saying,
A passionate but contemplative artist, struggling with issues crucial to cinema and society, Mizoguchi will continue to reward anyone who looks closely at his films. His awesome talent, self-discipline, and productivity guarantee this.
Ugetsu is one of Time's 100 Best Movies, #100 on the Arts and Faith list of 100 most spiritually significant films, one of the 1001 Movies You Must See Before You Die and one of Roger Ebert's Great Movies. FilmReference.com has a page on this film. Senses of Cinema has a review of this film as do Slant Magazine, the New York Times and Cinematical.