If we suspect a possible intracranial lesion, combined with the patient’s symptoms and neurological signs, the most convenient and quick way is to check a cranial CT, which can be done in a level 1 or level 2 hospital, and we can start with just a plain CT for about $200. After the CT is done, we have a preliminary judgment of the intracranial situation, and if there is a problem considering the possibility of a glioma, then we can further perform a magnetic resonance examination (MRI). MRI is what we usually call “nuclear magnetic resonance” or “MRI”, which is now called “magnetic resonance” in the unified standard. There are many sequences of MRI, including scanning (T1, T2) and enhancement, diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI), magnetic resonance spectroscopy (MRS), magnetic susceptibility weighted imaging (SWI), and perfusion imaging (PWI). For the diagnosis of cerebral breakthrough glioma, the most basic sequences of MRI should be checked for plain scan, enhancement, diffusion-weighted imaging (DWI), and wave (MRS) examination. By these basic sequences, most gliomas can be correctly diagnosed. If it is still difficult to make a definite diagnosis, then one can proceed to perfusion imaging (PWI), which is also a special sequence in MRI and not other examinations. Perfusion imaging is very valuable in identifying tumors, inflammation, or cerebral infarction. In addition, positron emission computed tomography (also known as PET) is also very useful in the diagnosis of glioma, which is a radionuclide labeling of substances that are essential to the metabolism of life, such as glucose and methionine. then the possibility of tumor is high. Moreover, the latest technology can fuse PET image results with CT or MRI images, which is also very important for localization and diagnosis. After these three tests, we will have a basic judgment of intracranial tumor, including location, size and nature, whether it is a tumor, what kind of tumor, benign or malignant. However, it should be noted that no matter how much the imaging examination looks like a tumor, the pathological diagnosis is the final diagnosis to clarify the tumor.