The study of body part metaphors provides a convenient way to examine human conceptual structuring because we start from what we as humans share. This study collected and compared Thai and English body part metaphors: one hundred and eighty-four English body part expressions and four hundred and eighty-eight Thai body part expressions were considered.The data are discussed in terms of the body part involved, the underlying conceptual metaphors, and syntactic and morphological form. The data show that basically, Thai and English share many conceptual metaphors, and there are a number of equivalent expressions in both languages, such as hua-hoog [head-spear] `spearhead', and waan-caj [sweet-heart] `sweetheart.' Furthermore, it was found that most body part metaphors are built on three different aspects of body parts: physical constitution, location and nature of involvement. In some contexts, more than one of these bases is involved in the same expression.Other similarities include sharing some of the same morphological and syntactic forms, using the same body parts; relative frequency of individual body parts; having completely equivalent expressions, and having pairs of opposite expressions. Differences involve having some different morphological and syntactic forms; the number of conventional body part metaphors found in translation-equivalent texts, with Thai having many more than English; a difference between the two languages in distribution across written vs. spoken texts; having similarly glossed expressions with different metaphorical meanings; level of markedness for an otherwise equivalent expression; and degree of explicitness in the components of an expression.Finally, applications of the findings to the teaching of English to Thai speakers and vice versa are discussed. I conclude that systematic attention to the bases of metaphorical expressions to facilitate learning is to follow the time-proven practice of linking the old to the new. / Department of English