Massive localized lymphedema (MLL) is a rare disease observed in people with morbid obesity. MLL is easily confused with soft tissue sarcoma. Therefore, MLL is sometimes called as pseudosarcoma in the literature. MLL was initially described by G. Farshid and S. Weiss in 1998. However, etiology of MLL is still unknown despite certain relationships with injuries, operations and hypothyroidism. Since the term «MLL» was introduced only 20 years ago, there are no reliable statistical data on the prevalence of MLL. According to the World Health Organization data (2016), 13% of the adult world population are obese. Therefore, the risk of MLL is increased in these people. Thigh is the most common site of lesion. Abdominal wall lesion is rare and can cause diagnostic difficulties due to large dimensions and appearance. We report a 50-year-old obese woman with MLL of anterior abdominal wall. She experienced discomfort while walking and sleeping due to giant MLL of anterior abdominal wall that significantly reduced quality of life. Removal of MLL (weight 22160 g) was followed by favorable cosmetic and functional outcome. Analysis of differences between MLL and soft tissue sarcoma in the era of «obesity epidemic» is valuable for correct diagnosis and treatment of this rare complication. This report is the first case of MLL, registered in Russia. In our opinion, this is associated with insufficient awareness of physicians about this complication of obesity. We hope our observation will help clinicians to identify and treat this complication.