This study analyzes the tonal variation of Lue dialects spoken in Thailand. These dialects are classified into groups based on structural differences in their tonal systems, and this classification then forms the basis for a linguistic map of Thailand’s Lue dialects. The data were collected from 45 villages in 7 provinces in the northern part of Thailand. Three informants were selected to represent each village, for a total of 135 informants participating in this research. William J.Gedney’s (1972) wordlist was used to elicit tonal data. The tonal features of the dialects were analyzed using auditory information and the personal computer programs “PRAAT, ver.4.5.12” and Microsoft Excel. 

My research categorizes the Lue dialects into two major classes with tonal systems consisting of, five and six tones, respectively. Deeper analysis of each dialect’s tonal system and tone features supports further division into nine basic patterns (patterns 1–5 with five tones and pattern 6–9 with six tones), with additional subdivisions in pattern 3, 5, 7, and 8. Furthermore, these nine basic patterns may also be organized into five groups based on the tone splits and mergers in column A of Gedney’s (1972) tone chart: 

(1) A1-2-3-4 (A1=A3, A2=A4), 
comprising patterns 1 and 6; 
(2) A1-23-4, comprising patterns 2 and 7, 
(3) A1-234, comprising patterns 3 and 8, 
(4) A12-34, comprising pattern 4; and 
(5) A123-4, comprising patterns 5 and 9. 

The tonal system and tone features of pattern 3/2 were found to be distributed widely in many provinces (Chiang Mai, Lamphun, Lampang, and Nan). The tonal system and tone features of patterns 5/1 and 8/2 are found in Chiang Rai province; and those of patterns 4 and 7/1, in Chiang Mai province.