Abstract: Mo Yan’s Frog revolves around the event of " family planning”. Through the narrator " I”, the novel tells the story of my aunt’s life and the countryside life related to the event. It successfully reproduces the ethical picture of China from the 1950s. Based on the major thread of " family planning” in Frog, analysis and deconstruction of four important ethical elements are realized from the perspective of ethical literary criticism so as to reveal the truth of life and get an insight into the inner ethical essence of the novel. These four important ethical elements include ethical environment, ethical choice, ethical identity and ethical consciousness.