Initial reviews for Twilight were generally positive, with Publishers Weekly called Meyer one of the most "promising new authors of 2005". The Times praised the book for capturing "perfectly the teenage feeling of sexual tension and alienation", and Amazon.com hailed the book as "[d]eeply romantic and extraordinarily suspenseful". Hillias J. Martin of School Library Journal stated, "Realistic, subtle, succinct, and easy to follow, Twilight will have readers dying to sink their teeth into it", and Norah Piehl of TeenReads wrote, "Twilight is a gripping blend of romance and horror". Publishers Weekly's starred review described Bella's "infatuation with outsider Edward", their risky relationship, and "Edward's inner struggle" as a metaphor for sexual frustration accompanying adolescence. Booklist wrote, "There are some flaws here–a plot that could have been tightened, an over reliance on adjectives and adverbs to bolster dialogue–but this dark romance seeps into the soul." Christopher Middleton of The Daily Telegraph called the book a "high school drama with a bloody twist ... no secret, of course, at whom this book is aimed, and no doubt, either, that it has hit its mark. Jennifer Hawes of The Post and Courier said, "Twilight, the first book in Stephenie Meyer's series, gripped me so fiercely that I called the nearest teenager I know and begged for her copy after I misplaced my own." Roberta Goli of Suite101.com gave the novel a positive review, saying that while "the first half of the novel lacks action", the writing is "fluid" and the story "interesting". She also praised the depth of emotion shown between the main characters for pinpointing "the angst of teenage love."
Kirkus gave a more mixed review, noting that, "[Twilight] is far from perfect: Edward's portrayal as monstrous tragic hero is overly Byronic, and Bella's appeal is based on magic rather than character. Nonetheless, the portrayal of dangerous lovers hits the spot; fans of dark romance will find it hard to resist." The New York Times review stated, "The premise of Twilight is attractive and compelling — who hasn't fantasized about unearthly love with a beautiful stranger? — but the book suffers at times from overearnest, amateurish writing. A little more "showing" and a lot less "telling" might have been a good thing, especially some pruning to eliminate the constant references to Edward's shattering beauty and Bella's undying love."  Although the Daily Telegraph later listed Twilight at number 32 on its list of "100 books that defined the noughties", it said that the novel was "Astonishing, mainly for the ineptitude of [Meyer's] prose". Elizabeth Hand said in a review for the Washington Post, "Meyer's prose seldom rises above the serviceable, and the plotting is leaden".
Twilight was on the American Library Association's (ALA) Top Ten List of the Most Frequently Challenged Books of 2010, for containing a "religious viewpoint" and "violence". The Twilight series was on the same list in 2009 for being "sexually explicit", "unsuited to age group", and having a "religious viewpoint". A NYC Psychologist addressed issues in the Twilight series and how it relates to women and expectations of healthy relationships versus illusion based relationships with her short film "Into The Twilight Haze".