The reflectivity, internal and external quantum efficiency, minority carrier lifetime and electrical characteristics of mono-crystalline silicon solar cells with double-layer and three-layer silicon nitride antireflection coatings are compared. The optical characteristics of double-layer and three-layer silicon nitride antireflection coatings are simulated. The results show that, the three-layer silicon nitride antireflection coating has a better antireflection effect and a better output characteristic. The double-layer and three-layer silicon nitride antireflection coatings are fabricated on P-type mono-crystalline silicon by the plasma enhanced chemical vapor deposition (PECVD) process. The analysis results of their antireflection and passivation effects show that the three-layer silicon nitride antireflection coating has a smaller reflectivity and a better passivation effect compared with the double-layer silicon nitride antireflection coating. The electrical characteristic testing results of the mono-crystalline silicon solar cells with double-layer and three-layer silicon nitride antireflection coatings show that the conversion efficiency of the mono-crystalline silicon solar cells with three-layer silicon nitride antireflection coating is relatively higher than that with double-layer silicon nitride antireflection coating.