OBJECTIVE: The primary aim of the following study is to find out the incidence of difficult intubation in obese and lean patients using IDS and secondary aim is to assess the performance of bedside screening tests to predict difficult intubation, mask ventilation and laryngoscopy in obese and lean patients.MATERIAL AND METHOD:A prospective, observational cohort study of 100 patients requiring general anesthesia were categorized into 50 each based on body mass index (BMI) into lean (BMI <25 kg/m2) and obese (BMI ≥25 kg/m2) groups. IDS score ≥5 was termed as difficult intubation. Pre–operative airway assessment included MMP score, mouth opening, thyromental distance, sternomental distance. Patients having difficulty in mask ventilation and laryngoscopy was recorded. RESULTS:Obese patients had a higher incidence of difficult facemask ventilation and laryngoscopy.  Physical status, prevalence of Comorbidities, neck circumference, SMD, and Mallampati index were higher in the obese group. Obese patients were slightly more difficult to intubate than lean. Age >40 years, NC >35 cm, SMD <12.5 cm and Comorbidities were factors which were associated with IDS ≥5. There was no significant difference regarding grading of laryngoscopy between the two groups.CONCLUSION: Obese patients are difficult to mask ventilate and slightly more difficult to intubate than lean patients but have no difference regarding laryngoscopy. It is preferable to have another skilled anesthesiologist while intubating an obese patient.