Abstract: In order to expose the effect of the fluoride-ardsenic exposure on the macroelements in serum of rat's offspring.The contents of macroelements in serum of rats'offspring were determined with the method of two generations-one nest reproductive test.The contents of Na⁺、Mg⁺⁺ and Ca⁺⁺ in the serum were decreased when incresed of exposed dose,but the changes of K⁺ and P⁺⁵ were not significant.After stopping the exposure for 8 weeks,the Na⁺、Mg⁺⁺、Ca⁺⁺ were increased distinctly.Fluoride-arsenic exposure can affect the levels of macroelements in serum of rats'off-spring.