Introduction: The nasal cavity and paranasal sinuses form an intricate and vital part of the human anatomy.Objectives: The main objective of the study is to find the morphometric study of the nasal cavity and paranasal sinuses and its implications for endoscopic sinus surgery. Methodology: This cross-sectional study was conducted at Navodaya Medical College hospital and Research Centre during October 2014 till December 2014. This morphometric study of the nasal cavity and paranasal sinuses was designed to provide comprehensive quantitative data on the anatomical variations within these structures. The study was conducted with a sample size of 85 patients, selected to represent a broad demographic range in terms of age, sex, and ethnicity. Male and female patients aged between 18 and 65 years who were to undergo ESS for sims, CRS, NP or SNM were enrolled in the study. Results: The study included 85 patients with a mean age of 42.01 ± 2.98 years, ranging from 18 to 65 years. The cohort was nearly evenly split by sex, with 52.9% males and 47.1% females. The average body mass index (BMI) was 25.4 kg/m², with values ranging from 18.5 to 32.5 kg/m².The mean anterior nasal cavity width was 22.5 mm, with a range from 18.0 to 27.0 mm, while the middle nasal cavity width averaged 18.7 mm, ranging from 14.5 to 23.5 mm. The posterior nasal cavity width had a mean of 13.6 mm, with a range of 10.5 to 16.5 mm. The nasal cavity height averaged 50.2 mm, varying between 45.0 and 55.0 mm, and the nasal septum length was found to be 55.8 mm on average, with a range from 50.0 to 61.0 mm. Conclusion: It is concluded that significant anatomical variability exists within the nasal cavity and paranasal sinuses, which has critical implications for endoscopic sinus surgery (ESS).