Anti-reflection film for a synthetic resin base comprises a first layer of silicon dioxide (SiO.sub.2) deposited on the synthetic resin base by evaporation, a second layer of alumina (Al.sub.2 O.sub.3) deposited on the first layer by evaporation, and a third layer of silicon dioxide (SiO.sub.2) or magnesium fluoride (MgF.sub.2) deposited on the second layer by evaporation. The first layer has a geometrical film thickness of 1 to 5 .mu., the second layer has an optical film thickness of .lambda./4, and the third layer has an optical film thickness of .lambda./4.