Introduction. Vision correction by contact lenses is one of the most common and effective methods for correcting refractive errors in children and adults. Compliance with rules of soft contact lenses (SCLs) wearing is one of the most important conditions for a safe use, while violation of compliance is usually the main cause of complications.Purpose. To study the structure of contact lens wearers by ametropia and lens wearing time as well as to determine the relationship between the incidence of giant papillary conjunctivitis (GPC) with lens wear time and overwear time.Material and methods. A retrospective analysis of 1 000 records (1 000 patients) of patients who underwent vision correction by SCLs in “Krugozor” ophthalmology clinic in the year 2019 was carried out. Mean age of patients was 24.95 ± 8.62 years. Age, type and degree of ametropia, material (hydrogel, silicone hydrogel or biocompatible hydrogel), lens replacement schedule, presence of complications, lens overwear time and daily wear time were taken into account.Results. Most SCLs users are patients between 21 and 30 years old (47%) who have a moderate degree of ametropia (52%). Most of them (46%) preferred monthly replacement SCLs, 29% – bi-weekly replacement SCLs, 9% preferred daily replacement lenses, while quarterly replacement lenses were used by 16%. Only 26.9% of SCL users complied with the instructions for lens wear, while for 29.4% of them lens overwear time amounted to up to 14 days, for 34.1% – up to 28 days, and for 9.6% – more than 1 month. More than half (56%) of patients mainly wore SCLs during 16 hours a day, one in five (22.7%) used SCLs during 12 hours a day, and 12.6% – up to 20 hours a day. 8.7% wore lenses during up to 7 days. The incidence of GPC in patients who did not comply with replacement schedule and were overwearing lenses was significantly higher (38.71%) than in patients who followed the replacement schedule (3.21%).Conclusion. More than half of the users comprised young people with a moderate degree of myopia. The most commonly used SCLs were monthly replacement. It was discovered that only one in four wearers followed recommendations of manufacturers and replaced lenses on time. Lens overwear may lead to a development of a giant papillary conjunctivitis (GPC).