From whole plants of Linaria japonica, four iridoid esters of D-glucopyranose were isolated. Iridolinaroside A is an iridoid ester on the 1-position of beta-D-glucopyranose, while iridolinarosides B-D are esters between two units of the same iridoid moiety and one molecule of D-glucopyranose. Since two iridoid moieties were esterified onto non-anomeric hydroxyl groups, iridolinarosides B-D were isolated as an anomeric mixture.