中文摘要：

文章研究了一类离散Hamilton系统次调和解的存在性．通过使用一种分解技巧，估计周期解的最小周期对应泛函的能量，得到Hamilton系统指定最小周期的次调和解存在性的一些充分条件．把这些充分条件应用到离散单摆方程中，可以得到单摆方程次调和解存在性的一些充分条件，改进了已有文献中的结果．

英文摘要：

By using a decomposition technique to estimate the energy of a solution in terms of the minimal period of the solution,we obtain some sufficient conditions for the existence of subharmonic solutions with prescribed minimal period of discrete Hamiltonian systems. When the results are applied to the discrete pendulum equation,some sufficient conditions,which are simpler to verify than those in the literature,for the existence of subharmonic solutions are obtained.