A method is disclosed for making an anti-reflection film of a solar cell. The method includes the step of providing a laminate. The laminate includes a ceramic substrate, a titanium-based compound film, a p+ type poly-silicon back surface field, a p− type poly-silicon light-soaking film and an n+ type poly-silicon emitter. The laminate is passivated with SiCNO:Ar plasma in a plasma-enhanced vapor deposition device, thus filling the dangling bonds of the silicon atoms at the surface of the n+ type poly-silicon emitter, the dangling bonds of the silicon grains at the grain boundaries of the p− type poly-silicon light-soaking film and the dangling bonds of the silicon atoms in the p+ type poly-silicon back surface field. Finally, the n+ type poly-silicon emitter is coated with an anti-reflection film of SiCN/SiO2.