With the acceleration of global population aging, mild cognitive impairment (MCI) has become a critical public health issue. As a non-pharmacological intervention, painting therapy exhibits unique advantages for community-dwelling older adults with MCI due to its non-verbal nature and multi-dimensional cognitive stimulation. This study systematically reviews the evidence base for painting therapy in this population and analyzes its mechanisms of action. These include neural mechanisms (e.g., regulating functional connectivity in brain networks like the default mode network to enhance neuroplasticity), cognitive mechanisms (activating multiple cognitive domains to build cognitive reserve), and psychosocial mechanisms (providing emotional expression and social interaction). Furthermore, the study classifies mainstream intervention models and compares their applicability in community settings. It also summarizes current limitations in research (e.g., small sample sizes) and practice (e.g., lack of professionals). Finally, based on a “hospital-community-family” framework, this study constructs the “Art Guards Memory” community support model. This model includes core components such as screening, intervention programs, talent support, and evaluation systems, alongside strategies for policy, resources, and sustained participation. The model aims to provide a scientific, standardized framework for applying painting therapy in community MCI intervention.