Homegardens are traditional farming systems which located within homesteads, continuously cultivated by and for households to ensure comprehensive household’s nutrient requirements as their main function. In this study, we investigated plant diversity, homegarden composition and the effects of distance from urban centers on plant diversity and composition in homegardens. Field surveys were conducted between October 2010 and October 2011 in three villages; Tham Lod, Mae La Na and Poong Yam, in Pang Mapha District, Mae Hong Son Province. In each village, at least 10 households were randomly selected. The owner of each homegarden was interviewed by a semi–structure method including vernacular name, used parts and method. A total of 243 plants species were recorded in this study. Most of them were used as foods (36.5%) and ornaments (24.9%). Additionally, the study has showed slightly negative effects of distance from urban center on plant diversity but showed more effects on plant similarities, particularly medicinal plants.