Epileptic seizures developing for the first time after a neurosurgical intervention (de novo seizures) are a challenge for choosing an optimal treatment. The pathogenesis of these seizures is often associated with factors that become inactive in the early postoperative period. These seizures can not serve the basis for diagnosing symptomatic epilepsy and should be regarded as a brain response to surgery, and patients do not need anticonvulsant therapy that reduces the quality of life. But in some situations, new early postoperative seizures serve the onset of symptomatic epilepsy and require prolonged anticonvulsant therapy. To date, one of the main techniques to identify the nature of newly developed seizure and to plan further treatment (whether or not to use anticonvulsant therapy) is video EEG monitoring. We present two clinical cases of patients who developed de novo convulsive seizures in the early postoperative period in similar situations after resection of intracerebral tumors. The use of video EEG monitoring allowed avoiding unreasonable use of anticonvulsant therapy in one of the patients.