AIM: The aim of the study was to Assess Knowledge and Attitude towards Obesity and Bariatric Surgery of Nurses at Tertiary Care Hospitals Lahore. Methodology: A descriptive cross-sectional research study design was used. Study used purposive sampling technique. The study population was staff nurses and sample size were 150. Result: The study was descriptive cross- sectional so descriptive statistic was applied, Frequency distribution was calculated, data normality was checked. The study reported that the poor knowledge about obesity participants were 54(36%), those with moderate were 52(34.7%), and those with good knowledge were 44(29.3%). The negative attitude about obesity participant were 40 (26.7%), those with average attitude were 58(38.7%), and those with positive attitude were 52(34.7%). the participants with good knowledge and positive attitude toward bariatric surgery where 47(30.9%), the participant of moderate knowledge and average attitude value where 53(34.9%), and those who with poor knowledge and negative attitude value where 50(32.9%). Conclusion: The study concluded that the majority nurses having poor knowledge, and average attitude regarding obesity and bariatric surgery.