OBJECTIVES The aim of our retrospective study is to analyze the relationship between type of operation and 30 days mortality following femoral neck fracture in the presence of different co-morbidities in patients aged over 60 years. METHODS Data were derived from the database of the National Health Insurance Fund Administration according to the ICD 10th revision's S7200 code. The study included patients aged over 60 years old discharged from inpatient care institutions following the primary treatment of femoral neck fractures. The patients with polytrauma were excluded from the study. Osteosynthesis was compared to arthroplasty as reference surgical method. Data were evaluated according to sex, age, type of fracture, patient turnover of institutions, surgical delay, early complications, hospital type, day of operation. The following co-morbidities were included into the analysis: C00-C97, D60-D64, E10-E16, F00-F99, G20-G26, G80-G83, I10-I15, I20-I25, I30- I52, I60-I69, I70, J00-J22, J40-J47, L89, N30-N39). Statistical analysis has been performed by logistic regression (Odds Ratio[95%CI], p<0.05). RESULTS Altogether 3783 patients were involved into the study. Type of surgical intervention (osteosynthesis/arthroplasty) OR: 1.7265, p: 0.0128. The following co-morbidities (ICD codes with OR and p value) proved to be statistically significant predictors: I10-I15: 2,0759(0.0136), I60-I69: 2.5104(0.0498), J40-J47: 2.8177(0.0305). CONCLUSIONS Osteosynthesis significantly increased the risk of 30 days mortality compared to arthroplasty. Osteosynthesis treatment of elderly femoral neck fracture proved to be statistically significant predictors of 30 days mortality: cerebrovascular disorders and chronic diseases of the lower respiratory system. A possible explanation of the difference in mortality can be that because of the higher risk of arthroplasty more healthy patients are selected for arthroplasty, while patient with poorer general health status undergo osteosynthesis having lower surgical risk.