Investigation on the effects of limiter biasing and applying external electric fields (positive and negative voltage of 200 V) under various pressures of 1.9, 2.3 and 2.7 Torr on the IR-T1 Tokamak plasma parameters such as plasma current, loop voltage, radial electric field, poloidal electric field and Reynolds stress and turbulent transports, was done in this work. The results show that the ramp time of the plasma current decreased and the change rate of loop voltage raised by increasing plasma pressure. The power of radial electric field is more than the power of poloidal electric field. According to the applied positive voltage to the plasma, it is observed that the Reynolds stress of IR-T1 Tokamak plasma has experienced a more significant reduction at the pressure of 2.3 Torr than other pressures. The results Also show that the applying positive voltage of 200 V to the IR-T1 Tokamak plasma at the pressure of 2.3 Torr (compared to other pressures) has more effect on increases and decreases the poloidal and radial turbulent transport, respectively.