Six　models　of　meso-microporous　materials　having　both　micropores　and　mesopores　are　numerically　constructed.　Effective　diffusion　coefficients　for　these　models　are　predicted　by　the　volume　averaging　method.　Solute　diffusion　coefficient　in　mesopores　is　assumed　to　be　much　larger　than　that　in　micropores.　Effects　of　equilibrium　distribution　constant,　the　ratio　of　diffusion　coefficient　in　mesopores　to　that　in　microporous　regions,　mesopore　shape　and　mesoporosity　on　the　diffusion　enhancement　originating　from　mesopores　are　discussed.　It　is　found　that　the　diffusion　enhancement　decreases　with　the　increasing　equilibrium　distribution　constant,　and　increases　with　the　increasing　mesoporosity　and　the　ratio　of　diffusion　coefficient　in　mesopores　to　that　in　microporous　regions.　The　influence　of　the　mesopore　shape　on　the　diffusion　enhancement　is　obvious　when　the　solute　equilibrium　distribution　constant　is　small,　but　the　influence　decreases　with　increasing　equilibrium　distribution　constant.　A　prediction　of　the　diffusion　enhancement　based　on　the　effective　medium　theory　agrees　reasonably　with　current　numerical　results.　(C)　2017　Elsevier　Inc.　All　rights　reserved.