According to existing research on the Yi people's calendar systems, there are mainly three types of Yi calendars: the Ten-Month Calendar, the Twelve-Month Calendar, and the Eighteen-Month Calendar. To this day, the Yi people continue to use their traditional calendars to guide daily life and agricultural production.

The Ten-Month Solar Calendar is widely used in the Yi-inhabited areas of Liangshan, Sichuan. The Yi people revere fire, and as the name suggests, the Ten-Month Calendar divides the year into ten months. Each month consists of 36 days, totaling 360 days for the ten months, with the remaining five or six days considered a special period for celebrating the New Year. Similar to the traditional Chinese lunar calendar, the Yi people also use animal names to mark years, months, and days. The Yi people refer to twelve traditional zodiac animals—horse, sheep, monkey, rooster, dog, pig, rat, ox, wolf, rabbit, dragon, and snake—as the "Primitive Twelve Nieneng." These twelve Nieneng represent years, dates, and times. Additionally, the seasons are determined by astronomical points (such as the Great Cold, Great Heat, Winter Solstice, Summer Solstice, Spring Equinox, and Autumn Equinox), accurately dividing the year into five seasons, known as the "Five Elements." Each element lasts 72 days, and the five elements collectively make up the 360 days of the year.

The Yi Twelve-Month Calendar is also highly regarded in the Yi-inhabited areas of Guizhou. This calendar is first mentioned in the book "Tulu Douji," preserved by the Bimo (priest) families of the Yi people in Guizhou. As the name implies, this calendar divides the year into twelve months, with each month consisting of exactly 30 days, totaling 360 days for the year. The remaining days, not belonging to any month, are considered a special period for celebrating the New Year. The Yi creation epic "Meige" also records this system: "There are twelve months in a year, each month for production; in the first month, we carry manure, in the second, we cut buckwheat stalks, in the third, we scatter buckwheat seeds, in the fourth, we harvest barley, in the fifth, we plant rice seedlings, in the sixth, we weed the seedlings, in the seventh, we harvest bitter buckwheat, in the eighth, we harvest rice and maize, in the ninth, we harvest sweet buckwheat and sow barley, in the tenth, we store grain in the granary, in the winter month, we sow wheat, and in the twelfth month, we cut firewood and prepare for the New Year." Therefore, the Twelve-Month Calendar is also an important reference for guiding the Yi people's agricultural production. However, due to its limited and scattered use today, its academic recognition is still debated. Nonetheless, it remains an important part of Yi cultural customs.

Another more ancient solar calendar, the Yi Eighteen-Month Solar Calendar, was scientifically validated much later as a traditional Yi calendar. In March 1990, Liu Yaohan, a researcher at the Chinese Academy of Social Sciences and a renowned Yi scholar, discovered the Yi Eighteen-Month Calendar during a field study in the Yagugeng Yi village in Tanhua Township. Calculations revealed that its origin predates the Ten-Month Solar Calendar. In the Eighteen-Month Calendar system, each month has 20 days, totaling 18 months. The remaining five days are designated as the Yi people's sacrificial days, during which they celebrate the New Year, worship totems, and pray for a prosperous year.

The traditional Yi calendars are timekeeping systems developed by the Yi ancestors through long-term observation, discovery, and summarization of production and life practices. They incorporate natural knowledge such as astronomy and geography, accurately recording and reflecting meteorological changes and phenological phenomena, and have great significance for guiding agricultural production and daily life. At the same time, they also reflect the diversity of Chinese civilization, and the Yi calendars have become a key to exploring the ancient cultures of ethnic minorities in southwestern China.