This article examines the legal status and professional responsibility of lawyers in the use of generative artificial intelligence (GenAI) in legal advisory and litigation practice. Situated within Vietnam's judicial reform, digital transformation and ongoing reform of the legal framework governing lawyers, the article argues that GenAI does not create a new legal profession. Rather, it requires a renewed interpretation of the core obligations that define lawyers' legal status in contemporary justice systems: independence, honesty, confidentiality, diligence, professional competence, loyalty to the client and candour before courts. Using doctrinal legal analysis, comparative legal research and policy-oriented synthesis, the article identifies major risks associated with GenAI, including inaccurate or fabricated legal authorities, algorithmic bias, disclosure of client data, erosion of independent professional judgment and diffusion of accountability between lawyers and technology providers. Drawing on experience from Singapore, the United States, the European Union, Canada and the United Kingdom, the article proposes that Vietnam should develop a risk-based professional responsibility framework for lawyers using GenAI through the Law on Lawyers, the Code of Ethics and Professional Conduct of Vietnamese Lawyers and guidance issued by the Vietnam Bar Federation. The proposed framework should focus on reasonable technological competence, data confidentiality, independent verification, conditional transparency, internal governance of law practices, and integrity in fees, advertising and information submitted to clients or courts. The article concludes that GenAI may improve access to and efficiency of legal services only where it remains subject to human professional judgment, institutional accountability and the ethical foundations of the legal profession.