The Phula speak a Sino-Tibetan language.  Specifically, it is in the Tibeto-Burman branch and is in an unclassified subgroup of Lolo-Burman.   Their language is a completely different language group from Vietnamese, which is of the Mon-Khmer group.  

    The language is probably related to Yi and Hani languages of  Yunnan Province, China.  It is sometimes called by other names, such as Phu Khla, or Fu Khla.  There has been great confusion at times because Phula is also an alternate name for the La Chi (Lati) people.  Though the language has recently gained the interest of scholars, little research has been conducted into Phula.  Like La Chi, the Phula language is possibly becoming extinct in Vietnam in some of the seven subgroups, who are slowly shifting to Vietnamese.

     Those subgroups living in Muong Khuong, Bac Ha, and Xin Man use Chinese characters in writing, and often converse in Han Chinese.

    Ropal code for the Phula language: PHH00