(57) The present invention relates to an electronic vaporization device and a vaporizer thereof. The vaporizer includes a liquid storage cavity and a heating assembly configured to heat and vaporize an aerosol-forming substrate in the liquid storage cavity. The heating assembly includes a first end surface facing the liquid storage cavity. The vaporizer further includes an isolating member including an isolating portion. The isolating portion is arranged between the heating assembly and the liquid storage cavity, covers the first end surface, and isolates the liquid storage cavity from the heating assembly. The isolating member further comprises a plurality of liquid guide holes provided in the isolating portion at intervals. The plurality of liquid guide holes are arranged through the thickness direction of the isolating portion. In the vaporizer, the heating assembly may be prevented from being in direct contact with the aerosol-forming substrate in the liquid storage cavity, thereby improving a vaporization effect, improving a vaporization taste, and reducing occurrence of liquid leakage.