AimsTo identify perceptions, attitudes, behaviours and barriers to effective obesity care among people living with obesity (PLwO) and healthcare professionals (HCPs) across mainland China.Materials and MethodsACTION‐China (ClinicalTrials.gov: NCT05428501) was a cross‐sectional, observational, descriptive, online survey‐based study of 7000 PLwO and 1000 HCPs (conducted between August and November 2022).ResultsThe majority of PLwO (76.8% [5374/7000]) and HCPs (94.6% [946/1000]) agreed that obesity is a chronic disease. Only 40.8% of PLwO (2853/7000) had discussed their weight or talked about losing weight with an HCP in the past 5 years. The most frequent reason given by PLwO for not discussing weight management with an HCP was believing it was their responsibility to manage their weight (34.7% [2430/7000]), whereas the most frequent reason HCPs gave for not discussing obesity with their patients with obesity was having more important health issues to discuss (72.1% [721/1000]). A smaller proportion of PLwO (19.1%) than HCPs (53.6%) felt that weight management discussions with an HCP would be very or extremely helpful for the patient, and 30.7% of PLwO experienced negative feelings after their most recent discussion. Overall, 34.8% (2438/7000) of PLwO had been diagnosed with obesity by an HCP, while 30.0% (2101/7000) of PLwO did not recognize that they had obesity.ConclusionsThis large, national survey conducted among PLwO and HCPs highlights key barriers to effective obesity care in China, including underestimation of weight status by PLwO and the need for increased communication between HCPs and PLwO regarding weight management.