PROBLEM TO BE SOLVED: To provide a flame retardant adhesive composition which forms an adhesive layer excellent in flame retardancy and also excellent in adhesiveness.SOLUTION: A flame retardant adhesive composition comprises an acrylic polymer, and a metal hydroxide having an average particle diameter of 10 μm or less and/or a hydrated metal compound having an average particle diameter of 10 μm or less. When the 180° peel adhesive force of an adhesive layer formed by a composition prepared by removing the metal hydroxide and the hydrated metal compound from the flame retardant adhesive composition is represented by an adhesive force A and the 180° peel adhesive force of an adhesive layer formed by the flame retardant adhesive composition is represented by an adhesive force B, a ratio of the adhesive force B to the adhesive force A (adhesive force B/adhesive force A) is 0.8 or more. The adhesive layer formed by the flame retardant adhesive composition has a flame retardancy of VTM-0 or VTM-1 in the flame retardancy test according to UL94 standards.