The invention provides an interlayer film for a laminated glass and a laminated glass, which are protected against a slump in TL value through attenuation of said coincidence effect and adapted to display an outstanding sound insulation performance over a broad temperature range. An interlayer film for a laminated glass comprising a plasticizer and a polyacetal resin, which is a blend of a polyacetal resin having an average polymerization degree of 1,000 to 3,000 and a polyacetal resin having an average polymerization degree of 3,000 to 5,000, and which has an acetalization degree of 60 to 85 mol % and an acetyl group content of 8 to 30 mol %. An interlayer film for a laminated glass which shows a temperature dependence of loss tangent in which the lowest-temperature side maximum of loss tangent appears at 30.degree. C. or lower when examined for dynamic viscoelasticity.