中文摘要：

考虑半空间中具有Navier边界条件的重调和方程组，文章结合积分不等式使用移动平面法证明了一个新的Liouville型定理．

英文摘要：

Consider the biharmonic system with Navier boundary value condition,we obtain a new Liouville type theorem for the system by the method of moving planes with integral inequalities.