Formaldehyde　(HCHO)　has　been　identified　as　one　of　the　most　common　indoor　pollutions　nowadays.　Manganese　oxides　(MnOx)　are　considered　to　be　a　promising　catalytic　material　used　in　indoor　HCHO　oxidation　removal　due　to　their　high　catalytic　activity,　low-cost,　and　environmentally　friendly.　In　this　paper,　the　progress　in　developing　MnOx-based　catalysts　for　HCHO　removal　is　comprehensively　reviewed　for　exploring　the　mechanisms　of　catalytic　oxidation　and　catalytic　deactivation.　The　catalytic　oxidation　mechanisms　based　on　three　typical　theory　models　(Mars-van-Krevelen,　Eley-Rideal　and　Langmuir–Hinshelwood)　are　discussed　and　summarized.　Furthermore,　the　research　status　of　catalytic　deactivation,　catalysts’　regeneration　and　integrated　application　of　MnOx-based　catalysts　for　indoor　HCHO　removal　are　detailed　in　the　review.　Finally,　the　technical　challenges　in　developing　MnOx-based　catalysts　for　indoor　HCHO　removal　are　analyzed　and　the　possible　research　direction　is　also　proposed　for　overcoming　the　challenges　toward　practical　application　of　such　catalysts.　©　2022　Institute　of　Process　Engineering,　Chinese　Academy　of　Sciences