Generally, in the field of motor control, voltage source inverters (VSIs) are considered to be superior to current sources inverters (CSIs). However, as the appearance of wide-bandgap (WBG) power semiconductors with high switching frequencies, CSIs are receiving more and more attention for Brushless DC (BLDC) motors. In this paper, a mathematic model of a three-phase CSI-fed BLDC motor and an effective sensorless control approach for high-speed BLDC motor driven by CSI is presented. The algorithm of line back electromotive force (back EMF) is used to detect the zero crossing points (ZCPs). Compared with conventional method of VSI, CSI shows its characteristics of inherent short-circuit protection and no need for consideration of dead-time. In addition, CSI provides the possibility to reduce the value of capacitance in low-pass filters and partially correct the commutation error. A method of closed-loop compensation based on line voltage difference integral is proposed to compensate the remaining commutation errors. The comparative simulation between CSI and VSI fed high-speed BLDC motor control system is carried out on MATLAB/SIMULINK platform and its results effectively verify the advantage of CSI applied.