AbstractThis paper is the first to explore tonal phonotactics in the world's natural languages. Zhangzhou Southern Min is theoretically assumed to have 7320 possible syllables but more than 71% of them are not empirically attested. Each lexical tone is logically possible to generate 915 syllables; however, the attested number only ranges from 98 syllables under tone 8 to 392 under tone 1. This study bases on a large corpus to explore how individual tones behave in the formation of attestable syllables, in what way tonal phonotactics occur and what mechanisms have trigged phonotactic constraints from both synchronic and diachronic factors. This study substantially stretches and advances our knowledge of tonal phonotactics as an important phonology phenomenon in this language. The exploration is supposed to serve as a model for thorough investigations of tonal phonotactics in Sinitic languages, shedding important light on the generalization of areal characteristics in Asia that possess rich and complex tonal contrasts. The study also contributes vital linguistics data to the typology of phonotactics in human languages, while enlightening a research direction of using experimental methods to model phonotactic restrictions in speakers' mental grammar and language practice.