Does Mongolia speak Chinese?

No.

The main language in Mongolia is Mongolian, with a small number of Kazakhs using Kazakh, Eastern European immigrants using Russian, and only some specialized Chinese learners speaking Chinese. Mongolian belongs to the Mongolian group of the Altaic language family, and its main speakers are the Mongols, who are facing the effects of serious sinicization of the Mongolian language used by the Mongols. It belongs to the Altaic family of adhesive languages.

Language feature analysis:

In March 2020, the Mongolian government officially adopted the National Outline of the Mongolian Script, deciding to fully revert to the use of the Huifeng-style Mongolian language from 2025 onwards, commonly known as the traditional Mongolian language. It is only 80 years since the abandonment of the migratory Mongolian script in 1946, and it seems as if everything is back to square one.

Mongolian is one of the lesser-known scripts in ancient history that has a definite founder and date. The Italian Roman Catholic, Plancarpin, wrote in his travelogue: "After Genghis Khan conquered the Mongols, he used their script and called it Mongol. For before this time the Mongols had no script of their own."