The toxicity of chromium in different valent are quite different. Cr (III) is a necessary trace element of human body, but excessive intake of Cr (III) may bring about health lesion. Cr (VI) is generally considered 1,000 times more toxic than Cr (III). Renal damge may happen when people contact or intake excessive chromium compounds. The renal function and the concentration of enzyme and protein may be changed. Kidney necrosis can happen in heavy cases. The metaboly of chromium compounds and its nephrotoxicity were reviewed in this paper.