PROBLEM TO BE SOLVED: To provide a food packaging bag as a food packaging bag for a triangle rice ball, allowing surely exposing only part of a food product to the outside while suppressing excessive opening when eating, and eating with good appearance while gripping the other packaging part of the food product.SOLUTION: A food packaging bag is such that: a bag body 1 having an opening 6 at a wide end side part side is formed through heat seals 4 and 5 of a narrow end side part and both inclined end side parts in a peelable manner by overlapping trapezoidal front and back films 2 and 3; a pair of opening projection pieces 7 and 8 are extended to the narrow end side part; and a sealing piece 9 wider than the bag body 1 is formed by extending an upper end part of the back film 3 from an opening end. When folding the sealing piece 9 on the front film and sticking by an adhesive layer 10, both end parts of the sealing piece 9 are projected from both inclined end sides of the bag body 1 to the outside so as to for
