The effects of host plants on survival,boring behavior,activity of cellulase,esterase and carboxylesterase of larvae of Monochamus alternatus Hope were investigated after the larvae were inoculated under the bark of five plants,Pinus massoniana ,P.thunbergi,P.taeda,P.elliottii and Cedrus deodara,respectively.The results showed that host plants significantly affected survival and boring behavior of larvae of M.alternatus. The survival of the larvae fed with P.massoniana was 100%,whereas it was 55.56% which fed with C.deodara. Activities of the cellulase,esterase and carboxylesterase of the larvae were significantly different among the five treatments.The activity of C_x of M.alternatus  fed on P.teada was the highest,which was (4.575 4±0.197 5) μmol ·g^-1(FW) ·min^-1,the activity of C₁ and β- l,4glucosidase of larvae fed on P.massoniana were the highest,which were (2819 9±0051 0)μmol ·g^-1 (FW) ·min^-1 and (3.079 3±0.173 3)μmol ·g^-1(FW) ·min^-1,respectively.The ctivities of esterase and carboxylesterase of the larvae fed on P.thunbergii and P.massoniana were the highest,which were 1 372.74 mmoD/min·μg and 744.82 .mmoD/min·μg,respectively.