To study the effect of zinc on mRNA expression of ZIP4 in human intestinal Caco2 cells and its regularity.Low zinc cell model was established by TPEN, a kind of chelating agent which chelates specially to zinc. ZIP4 cDNA fragment was obtained by RT-PCR. Expression of ZIP4 on 10 micromol/L TPEN exposure after 0, 2, 4, 6, 8 and 10 hours in Caco2 cells and its expression on various concentration of TPEN exposure (0,2.5,5,7.5 and 10 micromol/L) was measured by RT-PCR.A proper single fragment is obtained with the sequence conformable to the design. A proper single ZIP4 cDNA fragment was obtained. The mRNA expression of ZIP4 increased in accordance with the duration of low zinc. The peak mRNA level appeared at about 6h. And the ZIP4 mRNA increased in accordance with the concentration of TPEN in Caco2 cells.Zinc can regulate the mRNA expression of ZIP4 in Caco2 cells. And ZIP4 may play a role in the absorption of zinc in human intestine.