Objective This consensus aims to provide evidence-based recommendations on common questions in the diagnosis and treatment of acute respiratory failure (ARF) for critically ill cancer patients.Methods We developed six clinical questions using the PICO (Population, Intervention, Comparison, and Outcome) principle in diagnosis and treatment for critical ill cancer patients with ARF. Based on literature searching and meta-analyses, recommendations were devised. The GRADE (Grading of Recommendation Assessment, Development and Evaluation) method was applied to each question to reach consensus in the expert panel. Results The panel makes strong recommendations in favor of (1) metagenomic next-generation sequencing (mNGS) tests may aid clinicians in rapid diagnosis in critically ill cancer patients suspected of pulmonary infections; (2) extracorporeal membrane oxygenation (ECMO) therapy should not be used as a routine rescue therapy for acute respiratory distress syndrome in critically ill cancer patients but may benefit highly selected patients after multi-disciplinary consultations; (3) cancer patients who have received immune checkpoint inhibitor therapy have an increased incidence of pneumonitis compared with standard chemotherapy; (4) critically ill cancer patients who are on invasive mechanical ventilation and estimated to be extubated after 14 days may benefit from early tracheotomy; and (5) high-flow nasal oxygen and noninvasive ventilation therapy can be used as a first-line oxygen strategy for critically ill cancer patients with ARFs. A weak recommendation is: (6) for critically ill cancer patients with ARF caused by tumor compression, urgent chemotherapy may be considered as a rescue therapy only in patients determined to be potentially sensitive to the anticancer therapy after multidisciplinary consultations. Conclusions The recommendations based on the available evidence can guide diagnosis and treatment in critically ill cancer patients with acute respiratory failure and improve outcomes.