The Blue Lantern Corps is a fictional organization appearing in American comic books published by DC Comics, beginning in 2008 in Green Lantern vol. 4 #25 (January 2008) by Geoff Johns. Their powers, similar to those of other organizations based around the emotional spectrum, are fueled by the emotion of hope.

The Blue Lantern Corps is one of the nine corps empowered by a specific color of the emotional spectrum within the DC Universe, deriving power from the blue light of hope. The group was established by Ganthet and Sayd, who were banished from the Guardians of the Universe due to them willing to express emotions, unlike the other Guardians.

In the Rage of the Red Lanterns storyline, the Green Lantern Corps are ambushed by the Red Lantern Corps. Hal Jordan, reeling from the effects of an attack from Laira, is healed by Saint Walker. Walker introduces himself to the Green Lanterns as the Blue Lantern of Sector 1. Though John Stewart is suspicious of Walker's intentions, Walker's ring creates an illusion based on Stewart's psyche, freeing him from the effects of the Red Lantern attack that caused it. With Stewart placated, Walker takes Jordan to Odym. Ganthet and Sayd ask Jordan to aid the Blue Lanterns in rescuing Sinestro from Atrocitus, as his survival is important in the upcoming War of Light.

Jordan reluctantly accepts Ganthet's request and goes with the Blue Lanterns to the Red Lantern's base on Ysmault. Along the way, Walker tells Jordan that the Green Lanterns are nothing but a police force, and that Jordan would lead the Blue Lanterns like no other. Though Jordan tells him he has no intention of leaving his Corps, the reader observes Walker telling Warth that it was imperative that Jordan become a Blue Lantern. On Ysmault, Jordan locates Sinestro but is promptly ambushed by the Red Lanterns. He's captured by Atrocitus' forces, and though Atrocitus tells Laira that Jordan's flesh and blood belong to her, her attack is interrupted by the arrival of the Sinestro Corps. Chaos ensues, during which Walker and Warth come to Jordan's aid. They are shown not only boosting Jordan's power, but also capably handling the two battling Corps. Warth easily keeps the two from fighting one another, while Walker keeps Atrocitus himself at bay. During the conflict, Laira is killed by Sinestro. Outraged, Jordan attacks Sinestro and is so overcome with rage that Laira's red power ring chooses him as its new host.

After the conclusion of Rage of the Red Lanterns, the Blue Lanterns and Jordan return to Odym. Jordan is unable to remove the blue power ring and finds that it was interfering with the use of his green power ring. Ganthet explains to Walker that they did say Jordan would lead the Blue Lanterns, but not as a Blue Lantern himself. As a Green Lantern, Jordan's will would have been capable of charging the entire Blue Lantern Corps. Sayd says that a new blue power ring will need to be made for Walker, as they are unable to remove his original one from Jordan. Ganthet tells Jordan that, in order to remove the ring, he must use it by finding something to hope for. Jordan leaves for Oa, and Ganthet tells Walker and Warth that they must continue to recruit others to their Corps. The Blue Lanterns have a new mission: to locate those who wield the indigo light, for hope and compassion must work together. On Oa, the Guardians find that they are unable to remove the blue power ring from Jordan as well. During a later battle with Larfleeze, Jordan's blue power ring continues to repeatedly ask him what he hopes for. In frustration, Jordan says that he hopes that once the battle with Larfleeze is over that it will stop asking him what he hopes for. The blue ring registers this as a sincere hope, recharges all of the Green Lantern Corps' power rings, and allows Jordan to subdue Larfleeze. After Jordan gains control of his ring, it removes itself from him and leaves to find a new recipient in Sector 2828.

During the Blue Lanterns' struggle against Larfleeze, a number of black power rings come to Odym. Unable to detect any dead bodies on the planet's surface to attach themselves to, the rings hover in the sky, waiting for a death to occur. Under the influence of Jordan's green power ring, the Blue Lanterns' rings are charged by Jordan's willpower and capable of combating Larfleeze's constructs. The constructs suddenly disappear as Larfleeze finds himself being attacked by the reanimated corpses of his Orange Lanterns, now members of the Black Lantern Corps. Saint Walker, Ganthet, and Sayd join the team Jordan and Indigo-1 have assembled, and accompany them to recruit Larfleeze and Atrocitus. Despite saving him from the Black Lanterns, Larfleeze is resistant to join the group due to the nature of his power and an interest in obtaining his own Guardian. In order to secure his participation, Sayd offers him her servitude in return for his compliance.

While on Earth battling the Black Lanterns, Saint Walker's ring is activated by Ganthet to deputize Barry Allen as a Blue Lantern. The rest of the Blue Lantern Corps work with the Green Lantern Corps to destroy the millions of Black Lanterns coming from the destroyed planet Xanshi.

In September 2011, The New 52 rebooted DC's continuity. When Kyle Rayner becomes a 'magnet' for other power rings, Saint Walker is the only member of the other five Corps who shows up to help him rather than demanding his ring back, helping Kyle escape the others' attacks and travel to Oa to try and seek the aid of the Guardians. This plan backfires when it is revealed that Ganthet has been stripped of his emotions by the other Guardians, with him proclaiming that the Blue Lantern Corps was a mistake that he will now rectify. After Saint Walker returns to Odym, the Blue Lanterns are attacked by the Reach, enemies of the Lantern Corps, prompting Walker to send a desperate message for help to Kyle Rayner and the other New Guardians, while teaching other Blue Lanterns how to draw on their aura to enhance their defensive powers and fight back without a Green Lantern's presence.