A novel lighting balloon apparatus is provided for various indoor and outdoor lighting applications. The lighting balloon apparatus is comprised of a unique rectangular-shaped balloon envelope body constructed from a medium weight laminate of polyester film weaved into polyester fabric using an adhesive containing an antimicrobial additive and an ultraviolet inhibitor. The rectangular-shaped body of the balloon envelope provides a means for controlling the emission of light by allowing for the accommodation of lightweight taffeta panels without compromising control. The lighting balloon apparatus is further configured to accommodate multiple lighting sources, as well as applicable mixtures thereof. The various lighting sources that may be employed are securely coupled to a harness assembly suspended within the body center of the balloon envelope structure, which is sealed with a helium tight cap system and coupled to a relay bypass system for regulating multiple lighting source socket arrangements.