Eleven species of Thrixspermum are newly recorded from Thailand, three from sect. Thrixspermum: T. lampongense (Eastern floristic region), T. latisaccatum (Peninsular), and T. tortum (Peninsular); and eight from sect. Dendrocolla: T. anceps (Peninsular), T. bromeliforme (of unknown provenance), T. crassilabre (South-Western), T. duplocallosum (Peninsular), T. merapohense (Peninsular), T. pardale (Peninsular), T. patkaiense (Eastern), and T. pulchellum (Peninsular). Descriptions, photographs, and notes on distribution, ecology, phenology, vernacular names, and recognition are provided. Five species are considered to be uncommon in the wild: T. anceps, T. crassilabre, T. duplocallosum, T. patkaiense, T. tortum; and no precise localities are known for T. bromeliforme.