As language teacher well-being research has grown in popularity in the past decade, different models of conceptualisation and measurement have emerged, with PERMA being one of the most widely cited in the literature. However, its validity and suitability for the Chinese school context remain unclear. This study aims to validate and extend PERMA by contextualising it among high school English teachers in China. Data were collected from 408 teachers through an online questionnaire that included demographic information, the PERMA Profiler, and an open question. Confirmatory factor analysis was conducted to examine the cross-cultural validity and reliability of PERMA, and thematic analysis was used to identify new elements in well-being conceptualisation. The findings revealed complex results of the cross-cultural validity of PERMA. Answers to the open question extended the original conceptualisation of PERMA and revealed three new well-being concepts: low-arousal emotions, security and mindfulness. Implications for enhancing the use of PERMA among language teachers and for improving language teacher well-being are discussed.