Objective Clinical and pathological characteristics of triple negative breast cancer (TNBC) treatment are required for escalation or de-escalation of treatment because of a lack of druggable targets. This study aimed to identify the factors affecting the risk of disease recurrence and disease-related death in patients with TNBC. Methods Patients with TNBC who were treated at the University Medical Centre Maribor between January 2010 and December 2017 were studied. Clinical and pathological data were analyzed using multivariate analysis and non-parametric tests. Subgroup analysis was performed to examine additional factors that affect 5-year overall survival (OS) and recurrence-free survival. Results Multivariate analysis showed that tumor size and the lymph node ratio (LNR) were significant risks in our population. Better discrimination of patients at risk of a shorter recurrence-free survival and OS was achieved by using the LNR. Only lymphovascular invasion was significant for predicting 5-year OS. Conclusion For risk-based decision-making systems, the LNR is useful for discriminating between high- and low-risk patients with TNBC.