A system which build with using application can cover disadvantage on current system. Validation system and document legalized available today still has some disadvantage. With a system that utilizes E-Certificate application can cover and fix the system that is currently running. The design of the proposed system uses a digital signature algorithm RSA-2048 as the authentication mechanism. Furthermore, the validation and legalization system for e- certificate document has some advantages compared with current systems. System validation and legalized document using E-Certificate can ensure the authentication, data authenticity yet still efficient time (faster processing)