Chi Pai-Shih was one of the greatest artists in 20(superscript th) century. He had remarkable achievements on poem, calligraphy and ink painting. What makes his unique art style is that he imitates the spirits of old ways but not forms at all. His massive pieces caused the shams increased rapidly until now. Because of the number of ”flower-and-bird grass insect paintings” has the most part of his paintings and made him famous, this article attempts to analyze the style of ”flower-and-bird grass insect paintings” and refers to his artistic viewpoints first, finally inducts the ways of authentication about his paintings.