Background: Left thoracotomy and Belsey Mark 4 operation for diaphragmatic hernia repair considered another option for treatment. Aim of the study to present, strategy for treatment, operative technique and literature review. Methods: During a 20 year period a retrospective study took place. Seventeen(17) patients underwent left thoracotomy and Belsey Mark 4 operation for diaphragmatic hernia repair at Department of Thoracic Surgery, Oncological Hospital of Kifisia-Agioi Anargyroi, Athens Greece. Results: During the years 2001 to 2021, seventeen (17) patients 12 male 5 female underwent left thoracotomy and Belsey Mark 4 operation for diaphragmatic hernia repair, aged 33 to 76 years mean 55 years and hospital stay 4 to 7 days. All patients underwent preoperative gastro esophageal studies included ph studies, manometry and oesophagogastroscopy. The majority (70%) developed oesophagitis grade 3 -4. Also two of seventeen patients no significant oesophagitis diagnosed but reflux episodes reported. All these seventeen patients underwent left lateral thoracotomy, immobilization of oesophagus to aortic arch, hiatus mobilization fundoplication of oesophagus 2700 and Belsey Mark 4 procedure. No death or any other complication recorded. The hospital stay was 4 to 7 days. All patients underwent postoperative gastro esophageal studies included ph studies, manometry and oesophagogastroscopy. The majority of the patients had significant improvement. The follow up was from 1to 20 years mean 7 years. Only one male patient to seventeen did not attend. Conclusion: Left thoracotomy and Belsey Mark 4 operation for diaphragmatic hernia repair considered another option for treatment with lower complication rate. No thoracic pain has been recorded. Needs to be done by experience and well trained team.