To provide a tracking resistant flame-retardant adhesive tape having high flame retardance and excellently suppressing carbonization dielectric breakdown, without using a halogen-based flame retardant and an antimony-containing compound.

The flame-retardant adhesive tape is obtained by providing at least one side of a substrate with an adhesive layer comprising a flame-retardant adhesive composition prepared by adding 20-300 pts.mass of a phosphoric acid ester amide-based flame retardant to 100 pts.mass of an adhesive base polymer intentionally without adding halogen or antimony, or prepared by adding 20-300 pts.mass of a flame retardant containing a phosphoric acid ester amide-based flame retardant and a flame retardant containing neither halogen nor antimony other than phosphoric acid ester amide-based flame retardants based on 100 pts.mass of an adhesive base polymer.