Based on the think aloud method, this study examined the acceptance attitudes and psychological responses of 15 English learners from different backgrounds toward ChatGPT 4o’s English paraphrasing feedback. The results showed that learners generally demonstrated a high level of acceptance of the paraphrasing feedback, with an average acceptance rate of 81.85% across the three groups; ratings for writing style and content were 4.63 and 4.58,respectively. ChatGPT 4o provided diverse types of feedback, mainly involving lexical substitution, main clause rewriting, phrase replacement, and lexical addition. The findings suggest that ChatGPT 4o’s paraphrasing feedback may help learners reflect on language expression and content organization, offering insights for AI assisted English writing instruction.