The fructus of Gardenia jasminoides Ellis (GF) has been widely used as a natural colorant in Asian countries, and also as a Chinese traditional medicine for its homeostatic, antiphlogistic, analgesic, and antipyretic effects. In the present study, its main component, crocin, was fermented with lactic acid bacteria (LAB) and their antihyperlipidemic activity was measured. The GF extract, fermented GF (F-GF), crocin, and fermented crocin (F-crocin) significantly inhibited the increase of serum triglyceride (TG) level in corn oil feeding-induced triglyceridemic mice, as well as that of serum TG and total and LDL cholesterol levels in Triton WR-1339-induced hyperlipidemic mice. These agents also showed hypolipidemic activity in hyperlipidemic mice induced by high fat diet for 5 weeks. F-GF and F-crocin exhibited more potent hyperlipidemic effects than GF and crocin. The results suggest that the hypolipidemic effect of GF and crocin can be synergistically activated by LAB, and that F-GF and F-crocin may improve hyperlipidemia in clinic, compared with GF and crocin.