An induction of metallothionein by spinach extract was studied in mice. Among determined vegetables, the greatest effect was observed after injection of spinach extract. Injection of the extract induced metallothionein in a dose-dependent manner. Metallothionein was induced not only in the liver but in the kidney by injection of the extract. A fibrinogen level in the blood increased after injection of the extract. It indicates that cytokine may be involved in the induction of metallothionein by the spinach extract.