The present invention relates to an X-ray imaging apparatus, and more particularly, to an X-ray imaging apparatus in which a condenser is charged with low battery voltage, and the charged voltage of the condenser, or the sum voltage of the output voltage of the battery serially connected to the condenser and the charged voltage of the condenser is used as X-ray generating power. The X-ray imaging apparatus according to the present invention is configured such that the battery power and the condenser power are serially connected to provide power for operating the X-ray imaging apparatus, thus generating power for operating the X-ray imaging apparatus from the low battery power, and obtaining a lightweight and less bulky X-ray imaging apparatus. Further, the X-ray imaging apparatus according to the present invention senses the charged voltage of the condenser unit, and cuts off power being applied to the condenser charging unit from the battery when it is determined that the charging of the condenser unit is completed, thus reducing the power consumption of the battery.