This　study　presents　a　novel　group　Three-Way　Decision　(TWD)　method　that　effectively　addresses　decision-making　problems　characterized　by　interval-valued　uncertain　information　by　integrating　regret　theory　and　the　Consensus　Reaching　Process　(CRP)　model.　The　proposed　method　explores　several　key　principles　derived　from　regret　theory　to　transform　the　loss　functions　into　regret　theory-based　interval-valued　loss　functions.　Additionally,　improvements　are　made　to　the　TOPSIS　method　for　calculating　conditional　probabilities　of　alternatives　under　an　interval-valued　uncertain　environment.　Subsequently,　several　novel　interval-valued　TWD　rules　are　established　to　classify　alternatives　into　three　predefined　decision　regions　without　the　requirements　for　information　transformation.　Moreover,　a　personalized　CRP　model　is　developed　based　on　the　classification　results,　assisting　experts　with　low　consensus　in　revising　their　opinions　to　achieve　the　desired　consensus.　To　assess　the　effectiveness　of　the　proposed　method,　an　illustrative　example　is　presented,　accompanied　by　comparative　and　sensitivity　analyses　that　highlight　its　advantages　and　robustness.　The　results　emphasize　the　innovative　perspective　and　methodology　provided　by　the　proposed　method　for　effectively　addressing　practical　decision　problems　in　uncertain　and　risk-laden　environments.　IEEE