In　the　present　paper,　particle-to-fluid　convective　heat　transfer　coefficients　in　randomly　packed　beds　were　experimentally　investigated　by　the　naphthalene　sublimation　technique　and　the　heat-to-mass　analogy.　The　influence　of　the　entrance　effect　is　first　studied.　It　is　found　that,　the　Nusselt　number　in　the　entrance　is　lower　than　that　in　the　bulk　of　the　bed　and　when　the　flow　passes　through　6-8　particle　diameters,　the　heat　transfer　enters　the　fully　developed　region　where　the　Nusselt　number　remains　almost　unchanged.　The　Nusselt　numbers　in　the　fully　developed　region　are　then　compared　to　that　of　the　Wakao＇s　equation.　The　average　deviation　of　experimental　points　and　the　Wakao＇s　equation　is　11.83%.　Further,　the　applicability　of　Wakao＇s　equation　is　discussed　when　the　porosity　of　the　packed　bed　is　taken　into　consideration.　©　2016,　Science　Press.　All　right　reserved.