Taylor Swift is being dragged further into the Blake Lively and Justin Baldoni beef -- she just got hit with a subpoena in the case.

Sources with direct knowledge tell TMZ ... Baldoni's attorney Bryan Freedman has now subpoenaed Taylor as a witness in the Lively-Baldoni legal war.

Taylor's camp is blasting the subpoena, because they say she was minimally involved in the drama on the set of "It Ends With Us" ... which sparked a nasty legal war between Blake and Justin.

A spokesperson for Taylor tells TMZ … "Taylor Swift never set foot on the set of this movie, she was not involved in any casting or creative decisions, she did not score the film, she never saw an edit or made any notes on the film, she did not even see 'It Ends With Us' until weeks after its public release, and was traveling around the globe during 2023 and 2024 headlining the biggest tour in history."

The rep adds ... "The connection Taylor had to this film was permitting the use of one song, 'My Tears Ricochet.' Given that her involvement was licensing a song for the film, which 19 other artists also did, this document subpoena is designed to use Taylor Swift's name to draw public interest by creating tabloid clickbait instead of focusing on the facts of the case."

As we reported, Justin claims Taylor was more involved than just licensing a song, he says she gave a thumbs up to his casting of Isabela Ferrer as young Lily Bloom.

Plus, there is the issue of that critical meeting between Blake and Justin at her New York City penthouse, where they discussed a scene Blake had rewritten.

Justin has said the meeting got super heated, and he felt ambushed because Blake's husband Ryan Reynolds was there, and then Taylor showed up.

Taylor and Blake are close friends and after the meeting, Blake sent Justin a text message where she referred to herself as Khaleesi from "Game of Thrones," and Taylor and Ryan as her protective "dragons."