Paddy soil is suffering from serious heavy metal pollution due to rapid industrial and agricultural development. As the main food crop in South Asia and Southeast Asia, rice safety issues are particularly prominent due to increasing heavy metal pollution. The remediation of cadmium and arsenic-contaminated paddy soil has always been a complex issue because of the differences in their biogeochemical cycle. Our study reviews the research progress on in-situ passivation technology for paddy soil contaminated by cadmium and arsenic. We group the passivation technology into four types: redox type, microbial transformation and accumulation type, material immobilization type, and coupled passivation technology. Redox type passivation technology focuses on the migration and transformation mechanisms of Cd and As driven by Eh, pH changes, biogeochemical cycles of different elements, and organic matter under the influence of water regulation in paddy fields; microbial transformation and accumulation type passivation technology focuses on clarifying the mechanism of functional microorganisms on the absorption, transformation, compartmentalization and bacterial surface adsorption of arsenic and cadmium; material immobilization type passivation technology focuses on the classification of existing passivation materials and their immobilization mechanisms with cadmium and arsenic; coupled passivation technology focuses on summarizing the application analysis of synergistic passivation of cadmium and arsenic under the comprehensive system of the above three technologies. Also, we propose the forecast on the in-situ passivation restoration of paddy soils contaminated by cadmium and arsenic. Besides, the research direction of new mechanisms involved in the biogeochemical cycle of cadmium and arsenic in paddy soil, the innovation and extension trend of remediation technology are further discussed. We hope that a soil passivation improvement technology model will be created in future, which integrates modern agricultural production models with a guarantee of food production and security.