Aim: To determine the type and frequency of individual EGFR gene mutations in cases of lung cancer in the period from January 1, 2021 to April 1, 2023 at the Dubrava Clinical Hospital at the Clinical Institute of Pathology and Cytology. Methods: Results and data from the anamnesis were collected retrospectively from the laboratory information system Issa at the Clinical Institute of Pathology and Cytology. Data on age, gender and the results of EGFR mutation testing were collected. Epidermal growth factor receptor (EGFR) sequencing at Dubrava Clinical Hospital is performed using the Idylla™ RT-PCR system from paraffin blocks or cytological smears. Results: In the observed period, 251 patients diagnosed with lung cancer underwent molecular testing of the EGFR gene. In the majority of subjects (83,3%), the referring diagnosis was lung adenocarcinoma. Testing was performed on 140 cytological (55,8%) and 111 pathohistological samples (44,2%). Mutation was found in 57 (23%) samples, and this is more common in women (52,6%) compared to men (47,4%). The most frequently detected mutations are point mutation L858R and deletion in exon 19. In the tested women, there were more cases of lung adenocarcinoma with L858R and deletion in exon 19 between the ages of 61 and 70. In the tested men, the most frequent mutations were also L858R and deletion in exon 19, and this at the age of 71 to 80 years. Dana on cigarette comsumption habits were collected for 58,6% of tested patients, and it is evident that the majority belong to the categories of smokers and ex-smokers (77%), which indicates that smoking is a significant risk factor for developing and contracting lung cancer. Conclusions: The results of this retrospektive study point the importance of molecular testing of the EGFR gene in patients diagnosed with lung cancer, in order to receive targeted therapy as soon as possible, thereby improving of the outcome of treatment. The lack of data of the smoking status of a significant number of patients higlights the need for better documantation and monitoring of lifestyle habits that may affect the development of lung cancer.