Abstarct: The interaction of short pulsed laser with a solid body has become an important part of studies due to its many applications. Some of these applicationsr X-ray source, plasma particle accelerator, fast ion and fusion generation by inertial encapsulation, and etc. In such cases, non-linear effects will be very important, because it is the effects of high-intensity laser. In this study, with taking into acont Maxwell's equations and using hydrodynamic equations, behavior of high-frequency electromagnetic waves in plasma and under dense non-contact and non-magnetic studied and related charts have been drawn. Then we studied the emission of a P-pepolars electromagnetic wave in a sub-dense plasma, and obtained an optimum angle and absorption rate, and plotted changes in the electric and magnetic fields. Followed by adding an external magnetic field (homogeneous and heterogeneous) to check these behavior is discussed and plotted the diagrams of the changes in the electric and magnetic fields, as well as the absorption rate. We have shown that external magnetic field on the fields affected and they will increase and therefore the absorption rate is also increased.