While there has been a scholarly call to enhance authenticity in assessment in secondary English classrooms, whether and how secondary English teachers perceive authentic assessment (AA) and engage with it remains under-explored. Drawing on data gathered through survey, classroom observations and interviews, this study investigates the perception and practice of Chinese secondary English teachers with regards to AA. The findings show that while no participants denied the value of AA, only one-third of them admitted that they had tried to increase authenticity in their assessment tasks. The two teachers who implemented AA in practice had reaped benefits but noted ill alignment of AA with their curriculum. The findings also show that other impeding factors for the teachers' engagement with AA included high-stakes testing regime, limited resources, teachers' assessment literacy and misconceptions about students' abilities. Implications on how AA in contextualised classrooms could be better supported are also discussed.