Since the launch of ChatGPT in November 2022, teachers have received numerous AI-assisted or generated academic essays from university students. To explore postgraduate students’ perception and experience of using AI in academic writing, this study conducted a survey with a class of 40 postgraduate students studying English language and literature in Hong Kong. Participants were invited to share their perspectives and experience of using AI in academic writing. Then, toward the end of the course, 6 postgraduate students were invited to join a focus-group interview and submit their AI-assisted English essays. A close evaluation was conducted to assess the accuracy and credibility of the content, in-text citations, and references in the collected AI-assisted essays. Findings reveal that generative AI can only produce academic writing of limited quality. Users of AI are advised to pay attention to the translation of proper names, and the credibility of the content, in-text citations, and references provided by AI.