Аннотация:Background: Spirometry is a universal, simple, and non-invasive pulmonary function test. Spirometry, along with calculation of the forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC), is helpful for diagnosing obstructive or restrictive lung disease. Postoperative Pulmonary Complications are defined as unintended pulmonary abnormalities that occur as a result of surgery which cause identifiable dysfunction. Purpose: To find the evidence showing the importance of pre-operative PFT to predict risk of pulmonary complications after abdominal surgery Methodology: The study was conducted according to Preferred Reporting Items for systematic reviews and meta-analysis guidelines. Evidences selected since year 2002- 2020 from PubMed, Google Scholar, Physiotherapy Evidence Database (PEDro), ResearchGate and ScienceDirect. Key words used were: Pulmonary Function Tests, Post-Operative Pulmonary Complications, and Abdominal Surgery. Analysis was done using 2 scales: Centre for Evidence-Based Medicine Levels of Evidence Scale. Total 12 articles were found. Among them 10 were selected. Results: 5 articles showed that preoperative PFT is important in prediction of PPCs while the other half concluded that routine preoperative spirometry is not necessary before non-thoracic surgeries. Conclusion: Based on evidences, in the nutshell it is reviewed that there is controversy regarding the value of preoperative pulmonary functions test in non-thoracic surgeries. Keywords: Pulmonary Function Tests, Post-Operative Pulmonary Complications, and Abdominal Surgery