The utility model provides a range hood's smoke deflector elevating system, includes mounting bracket, actuating mechanism, lifter and smoke deflector, and actuating mechanism installs on the mountingbracket, and smoke deflector installs the lower extreme at the lifter, and actuating mechanism drive lifter and smoke deflector do elevating movement, its characterized in that: actuating mechanism is electric capstan mechanism, and the lifter has two and locate the left and right sides of mounting bracket at least, and electric capstan mechanism has two power take off ends, and these two power take off ends are located the left and right sides of mounting bracket respectively to, the power take off end can drive the lifter of both sides and do synchronous elevating movement. The utility model has the advantages of: this smoke deflector elevating system's actuating mechanism adopts electric capstan mechanism, and two power take off ends of electric capstan mechanism are located the left and right sides of mounting bracket respectively, and synchronous elevating movement is done to the lifter that the power take off end provided the power of up -and -down motion and drove both sides, and then makes smoke deflector can keep smooth motion.