The increasing number of magnetic resonance imaging (MRI) studies could lead to delayed or missed diagnosis of significant brain pathologies like high-grade gliomas (HGG). Artificial intelligence methods could be applied in analyzing large amounts of data such as; brain MRI studies. In this study we aimed to propose a convolutional neural network (CNN) for the automatic detection of HGGs on T2-weighted MRI images.A total of 3580 images obtained from 179 individuals were used for training and validation. After random rotation and vertical flip, training data was augmented by factor of 10 in each iteration. In order to increase data processing time, every single image converted into a Jpeg image which has a resolution of 320x320. Accuracy, precision and recall rates were calculated after training of the algorithm.Following training, CNN achieved acceptable performance ratios of 0.854 to 0.944 for accuracy, 0.812 to 0.980 for precision and 0.738 to 0.907 for recall. Also, CNN was able to detect HGG cases even though there is no apparent mass lesion in the given image.Our preliminary findings demonstrate; currently proposed CNN model achieves acceptable performance results for the automatic detection of HGGs on T2-weighted images.