This　article　introduces　the　concept　of　ecological　costs　associated　with　the　waste　paper　recycling　system.　The　costs　associated　with　this　process　include　resource　consumption,　waste　emissions,　ecological　damage,　and　production　processes.　To　analyze　the　ecological　costs　of　deviations　from　the　baseline　material　flow　in　a　waste　paper　recycling　system,　a　benchmark　material　flow　diagram　is　constructed　using　the　material　flow　analysis　method.　The　diagram　illustrates　a　fully　closed　one-way　material　flow　of　the　recycling　system,　which　is　highly　abstracted　and　simplified.　The　study　analyzed　the　ecological　costs　of　the　benchmark　material　flow　and　the　impact　of　deviations　from　it.　The　results　suggest　that　the　circulation　of　materials　within　and　between　processes　increases　the　ecological　cost　of　the　waste　paper　recycling　system.　Furthermore,　the　release　of　materials　from　a　process　into　the　environment　also　contributes　to　its　ecological　impact.　However,　the　introduction　of　external　materials　into　the　recycling　system　can　reduce　its　ecological　impact,　particularly　if　these　materials　are　recycled　resources.　The　study　emphasizes　the　significance　of　considering　ecological　costs　in　waste　paper　recycling　systems　to　minimize　their　environmental　impact.