Provided is a film or sheet composed of a resin composition that includes a poly lactic acid (A), an acidic functional group-modified olefinic polymer (B) including an acidic functional group and having an acid value of 10 to 70 mg KOH/g and a weight average molecular weight of 10,000 to 80,000, a tetrafluoroethylene polymer (C), and an aromatic cyclic phosphazene-containing flame retardant (D) including a compound of General Formula (I) and in which the aromatic cyclic phosphazene-containing flame retardant (D) is included in an amount of 10 to 70 parts by weight based on 100 parts by weight of the poly lactic acid (A), and a method for manufacturing the film or sheet by melt film formation. Each sign in Formula is as described in the specification.