Abstract: In this work, there is a comprehensive Theoretical formalism for the generation of THz radiation with the use of two femtosecond laser pulses on applying the d.c. electric field in a magnetized collisional plasma. Due to filamentation action of femtosecond pulses in magnetized collisional plasma, there occurs non Linear coupling in transverse d.c. electric field. In this mechanism, non-linear electromagnetic force leads to non Linear transverse oscillatory current that excites at resonance to generate THz radiation. The amplitude of THz radiation can be increased by increasing magnitude of magnetic field.