Microplastics　(MPs)　are　small　plastic　pieces　less　than　5　mm　in　size.　Previous　studies　have　focused　on　the　sources,　transports,　and　fates　of　MPs　in　marine　or　sediment　environments.　However,　limited　attention　has　been　given　to　the　role　of　land　as　the　primary　source　of　MPs,　and　how　plastic　polymers　are　transformed　into　MPs　through　biological　or　abiotic　effects　during　the　transport　process　remains　unclear.　Here,　we　focus　on　the　exploration　of　the　main　sources　of　MPs　in　the　soil,　highlighting　that　MP　generation　is　not　solely　a　byproduct　of　plastic　production　but　can　also　result　from　the　impact　of　biological　and　abiotic　factors　during　the　process　of　MPs　transport.　This　review　presents　a　new　perspective　on　understanding　the　degradation　of　MPs　in　soil,　considering　soil　as　a　distinct　fluid　and　suggesting　that　the　main　transformation　and　change　mediated　by　abiotic　factors　occur　on　the　soil　surface,　while　the　main　biodegradation　occurs　in　the　soil　interior.　This　viewpoint　is　suggested　because　the　role　of　some　abiotic　factors　becomes　less　obvious　in　the　soil　interior,　and　MPs,　whose　surface　is　expected　to　colonize　microorganisms,　are　gradually　considered　a　carbon　source　independent　of　photosynthesis　and　net　primary　production.　This　review　emphasizes　the　need　to　understand　basic　MPs　information　in　soil　for　a　rational　evaluation　of　its　environmental　toxicity.　Such　understanding　enables　better　control　of　MPs　pollution　in　affected　areas　and　prevents　contamination　in　unaffected　regions.　Finally,　knowledge　gaps　and　future　research　directions　necessary　for　advancements　in　this　field　are　provided.　©　2023　The　Authors