To provide pesticides such as insecticides, miticides and nematicides, which are excellent in the safety, pesticidal effects, residual effectiveness, etc., which further have infiltration, and which can be applied by soil treatment.A pesticide comprising a 3-alkoxy-1-phenyl-pyrazole derivative represented by the formula [I] or an agriculturally acceptable salt thereof as an active ingredient: wherein, for example, R1 is a C1-C10 alkyl group or the like, R2 is a hydrogen atom or the like, R3 is a hydrogen atom or the like, and each of R4, R5, R6 and R8 which are independent of one another, is a hydrogen atom or the like, and R7 is a C2-C4 haloalkylthio group or the like.