Objectives. To evaluate the influence of the use of sodium fluorescein (FLS-Na) in surgery of glioblastoma (GB) on the degree of tumor resection and survival in patients treated at the National Institute of Neoplastic Diseases. Materials and methods. A total of 238 cases of GB treated between 2008 and 2013 were reviewed and 150 cases of GB who underwent surgical resection with clinicopathological information and adequate follow-up were selected. Results. The mean age was 51 years, 58.7% of the cases presented a Karnofsky score of at least 90. FLS-Na was administered in 80 cases (53.3%) and a subtotal and total resection was obtained in 69 (46%) and 81 (54%) cases, respectively. The group that received FLS-Na obtained higher rates of total resection than the group operated with white light alone (77.5 vs 27.1%, p<0.001). The median overall survival (OS) was higher in the group subject to total compared to subtotal resection (17 vs 7 months, p<0.001). The median OS in those who received FLS-Na was higher than in those who did not (15.0 vs 8 months, p=0.003). Other factors affecting OS were age (p=0.002), the Karnofsky score (p=0.052) and radiation therapy (p=0.016) and chemotherapy (p=0.011). Conclusions. The microsurgical technique with administration of FLS-Na was associated with an increase in the rate of total resection and survival.