中文摘要：

设图G不含与2K1＋K2同构的导出子图，并且不含导出4-圈，通过对该图类独立数的讨论，刻画出它的结构，从而得到该图类色数与团数有关的线性的上界．

英文摘要：

In this paper, the structural characterization of {2K1 ＋ K2, C4}-free graphs was given according to their independence numbers, and the linear upper bound on chromatic number of {2K1 ＋ K2, C4}-free graphs was obtained in terms of their clique number.