Hiatial Hernia (HH) is one of the most freqent diseases of the esophagus. Selecting the implant material when operating on large hiatial hernias is still an issue. The question of positioning the cuff (during Nissen operation) in the abdomen rather than the mediastinum is also under discussion. This observation demonstrates a patient who was twice operated on in one of the European clinics. Initially in 2009 the patient underwent anterior and posterior hiatoplasty, formation of Nissen’s cuff while crurorhaphy was conducted using no prosthesis. Later in 2014 for recurrent hernia a fortifying plasty was made using a Crurasoft Patch mesh implant. In year 2017 patient consulted a surgeon complaining of recurrent reflux. Diagnostics revealed the migration of the cuff into the mediastinum along the smooth side of the implant. Prosthesis was replaced, the cuff was relocated back into the abdomen. Conclusion. The observation shows that Nissen’s cuff was effective while located in the abdomen and as it migrated to the mediastinum antireflux capacity decreased. Using a double-sided implant may lead to the migration of the cuff along the smooth side.