Aim and objective: Medicinal plants, their biological activities, and their phytochemical contents are important for finding safe and potent new compounds for therapeutic use. In order to investigate the chemical contents and to evaluate the storage effect on the antioxidant activity of Lebanese Annona squamosa (AS) leaf essential oil, the current study was undertaken. Methods: Shade-dried leaves of AS were taken from Batroun (Lebanon), and the essential oil (EO) was extracted by hydrodistillation. The gas chromatography-mass spectrometry (GC-MS) technique was used to analyze the composition of the EO. Concerning the antioxidant activity, two different methods namely radical scavenging activity (DPPH test) and ferric reducing antioxidant power (FRAP) were used. Results: A total of 21 compounds were identified. The majority of the identified compounds belong to sesquiterpenoids. β-elemene (11.39 -14.14 %) and β-carophyllene (10.15 – 15.56 %) were the most abundant components. On the other hand, the storage of the plant materials containing the EOs or the EOs themselves leads to a loss in the volatile compounds, which is reflected in the bioactivity as shown in the results of the antioxidants assays. The EOs demonstrated antioxidant activities with IC50 lower than 9 μg.mL-1. DPPH test and FRAP test exhibited a strong positive correlation (r=0.99). Conclusion: The obtained results suggest that EO extracts from AS have an antioxidant to protect people. Thus, the EO of fresh samples of AS can have interesting applications in versatile areas such as the pharmaceutical and food industries. Peer Review History: Received: 27 April 2022; Revised: 11 June; Accepted: 29 June, Available online: 15 July 2022 Academic Editor: Dr. Marwa A. A. Fayed, University of Sadat City, Egypt, maafayed@gmail.com UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file: Reviewer's Comments: Average Peer review marks at initial stage: 6.0/10 Average Peer review marks at publication stage: 7.5/10 Reviewers: Dr. Marwa A. A. Fayed, University of Sadat City, Egypt, maafayed@gmail.com Dr. Sangeetha Arullappan, Universiti Tunku Abdul Rahman, Malaysia, sangeetha@utar.edu.my Dr. Nazim Hussain, North East Frontier Technical University, Arunachal pradesh, India, nhussain116@gmail.com Similar Articles: GC-MS ANALYSIS OF FIXED OILS OF NIGELLA SATIVA SEEDS