The invention provides a wind speed and direction calibration system suitable for low pressure conditions. The system comprises a to-be-calibrated wind speed sensor, a vacuum ring mold system, a speed-adjustable rotation station system, a cantilever, a stepping motor and a stepping motor controller. Movement of the sensor relative to the air is realized through certain-speed rotation, the sensor angle is controlled through the stepping motor and a shaft coupling for realizing wind direction simulation so as to realize two-dimensional wind direction simulation. The system is advantaged in thatcalibration of a double wire hotline wind speed sensor is realized based on equipment in the prior art, the structure is simple, reliability is high, and test efficiency is effectively improved.