New CD re-issue on the Baked Goods label. Bug is the third studio album originally released in 1988. It was the last Dinosaur Jr. album with original bassist Lou Barlow until Beyond in 2007. NME critic Jack Barron deemed Bug "the most comprehensive rock statement of the year so far" in a 1988 review for the magazine, noting Dinosaur Jr.'s predominantly "torpid" approach and commenting that the music "trepidates everyday reality away", while rating the album "8.999999" on a ten-point scale.

In a retrospective review of Bug for AllMusic, Stephen Thomas Erlewine described "Freak Scene" as the album's "masterpiece" and opined, "Although the majority of the album is firmly situated in the sprawling, noisy metallic fusion of hard rock and avant noise, Bug also demonstrates that J Mascis has a talent for winding folk-rock". While finding its songs "quite uneven", Erlewine concluded that the album nonetheless constitutes "a major step forward for Mascis".

Writing for Drowned in Sound in 2005, Mike Diver said of Bug, "The songwriting has increased tenfold since You're Living All Over Me ... really, if you like music – be it grunge, indie, punk, whatever – you will love this. Period. Go spend some money already." Keith Cameron of Mojo wrote, "Bug marks the emergence of Mascis writing by rote. When applied to such an outlandishly great song as 'Freak Scene' his skills still blazed, however, and as formulaic exercises in discordant alienation go, Bug is better than most.