The work aims to develop an eco-environment and efficient microencapsulated red phosphorus preparation and modification method. Ethyl alcohol and distilled water were used as solvent and non-solvent respectively and ethyl cellulose was selected as shell material to prepare microencapsulated red phosphorus (ECRP) by phase separation method. Then, tetra-ethoxysilane (TEOS) was introduced as the modifier to prepare SiO2/EC composite shell microencapsulated red phosphorus (Si-ECRP) by sol-gel method. Several groups of Si-ECRP samples were prepared by changing the addition of TEOS and the morphology and performance of the samples were characterized to determine the optimal process condition. ECRP prepared by phase separation method had good coating effects and possessed a coating ratio of 86.5%. The moisture ratio after 10 days de-creased to 6.8% and improved obviously when compared with the ratio of pristine red phosphorus of 24%. The thermal and mechanical stability of ECRP increased, the ignition point reached 300 ℃ and the friction sensitivity decreased to 34%. As the addition of TEOS increased, the shell structure of three groups of Si-ECRP transferred from composite to double-layer. When 1 mL TEOS was used as the optimal condition, Si-ECRP got a composite shell material and the coating ratio was 94.2%. The ignition point of Si-ECRP was 100 ℃ higher than that of ECRP. The friction sensitivity of Si-ECRP decreased by 14% and reached 20%. Therefore, Si-ECRP had more excellent properties. ECRP can be prepared by phase separation method under normal temperature and neutral environment. In addition, the raw materials are all environmental materials and the method is simple and efficient. On the basis of ethyl cellulose shell forming mechanism, the Si-ECRP preparation process is simplified and SiO2/EC composite shell structure is prepared, so the performance of pristine has been improved further.