An atomization core, an atomizer, and an electronic atomization device are provided. The atomization core includes a porous substrate and a heating element. The porous substrate is a porous glass-ceramic substrate. The porous glass-ceramic substrate includes a first measurement area and a second measurement area. By atomic percentage, a main element content in the first measurement area is denoted as M %, and a corresponding main element content in the second measurement area is denoted as N %, where |MN|/M is less than 10% and/or |MN|/N is less than 10%. The length of the measurement area is greater than 1 m. The main element is an element more than 20% in the porous glass-ceramic substrate.