The MBF-P03 Gundam Astray Blue Frame is a Mobile Suit introduced in the manga series Gundam SEED Astray and featured in the photo-novel Mobile Suit Gundam SEED Astray B. It is piloted by Gai Murakumo.

The MBF-P03 Astray Blue Frame was one of five identical prototype combat mobile suits developed using stolen data from the Earth Alliance's G Project and was designated for testing optional equipment. Its computer contains data and blueprints for various optional equipment. Most of the technology from the G Project was successfully copied with the exception of Phase Shift armor. In its place the Astrays' designers made the machines out of a lighter foaming metal compound and were built with minimal armor over the frame. This made the Astray mobile suits lighter and faster than their G Project counterparts.

Originally, the Astray Blue Frame was armed with the standard armament of the other prototype Astray suits. These weapons include two head-mounted "Igelstellung" 75mm multi-barrel CIWS, two back-mounted beam sabers for close combat, a Type 71 beam rifle, and a single physical shield. However its mercenary pilot used his resources to outfit the Astray Blue Frame with a wide variety of equipment to suit multiple combat situations and to meet the needs of different mission. Like the other prototype Astray suits, Astray Blue Frame's backpack can be lowered to the back skirt armor, allowing the mounting of additional equipment on its back.