A method and an apparatus for diagnosing a brain tumor in real-time are disclosed. A method for detecting a brain tumor in real-time can comprise the steps of: generating, by a probe, a plurality of input signals and transferring the same to a target detection region which is estimated to be the location of a brain tumor； receiving, by the probe, a plurality of reflection signals on the basis of a plurality of input signals； and detecting, by the probe, a plurality of the received reflection signals, wherein a plurality of the input signals comprise a terahertz signal, an optical coherence tomography (OCT) signal, and a Raman signal, and a plurality of the reflection signals can be used for generating a plurality of image information for detecting the location of a brain tumor； and an apparatus for diagnosing a brain tumor in vitro and in real-time, can be used to diagnose, in real-time, a brain tumor specimen, which is extracted from the brain.
