This article makes further exploration on the historical origin and cultural value of Yi people's Four-Square and Eight-Digit from the perspective of ethnic history and culture. The identification of Yi people's Four-Square and Eight-Digit with profound historical and cultural information not only has a long history，but also contains knowledge of ancient geometry mechanics，astronomy and calendrical calculation. It is Yi ancestors' objective cognition of living environment，original understanding of space-time and organic combination of astronomy and calendar, which has the historical and cultural value as 'living fossil'.