Moria gives it 4 out of 5 stars and calls it "an important genre landmark". Slant Magazine gives it 3 out of 4 stars and says, "Some 30 years after its original theatrical release, this schlocky extrapolation of Ingmar Bergman's The Virgin Spring is still the definitive horror-film-as-cautionary-tale." 1000 Misspent Hours opens its review with this: "If there is any one movie that can be taken to symbolize the trend toward utterly unapologetic viciousness in the horror films of the 1970’s, Wes Craven’s The Last House on the Left is probably it."
HorrorNews.net says, "It’s tricky and nasty and scary and vengeful and heartbreaking and strange. It is light and dark, fast and slow, happy and angry and sad and silly. It has moments that are incredibly hard to watch and I wouldn’t recommend this to just any audience as I don’t know that they would be able to handle it." DVD Talk says, "The Last House on the Left is first and foremost an exploitation film." DVD Verdict says it's still "mostly an effective film" but warns, "Last House on the Left is not a fun film; it might not even be called "entertaining." It's certainly not a Friday night popcorn flick (at least not for most people). The plot is horrifying, the violence graphic, and the outlook of the film pretty bleak."
Roger Ebert likes it, gives it 3 1/2 out of 4 stars and calls it "a tough, bitter little sleeper of a movie that's about four times as good as you'd expect." Rotten Tomatoes has a critics score of 51% and an audience rating of 51%.