A method for manufacturing insole uses used footwear and recycled wooden articles are primary ingredients, which are pulverized to form particles of the recycled materials. The recycled wood, taking a ratio of weight of 15-35%, is uniformly mixed with matrix rubber that functions to adjust physical properties and foaming agent, and then pressed to form an insole material in a sheet form, which is deposited in a mold to be heated and pressurized for curing and setting thereby forming an insole featuring proper resilience and anti-bacteria and deodorization. The use of the insole is thus completely sanitary and comfortable and also features pollution- and nuisance-free use by repeated use in the sense of environment conservation.