Safety accidents have occurred in many counties and construction sites. Sometimes, it seemed to be inevitable items during construction work. However, these safety accidents imply lots of influence construction projects in terms of cost and schedule. To prevent the safety accident in construction project, this paper proposes the work task based safety management system that is consisted of safety information combined with daily based work task schedule and mobile technology such as personal digital assistant (PDA). The daily based work Task Safety Management System (TSMS) in the construction phases has been applied to over 200 projects for 24 months. Comparing before and after using TSMS in number of injuries and number of deaths, usability of TSMS was verified. This paper contributed to create new system which were based on daily based work tasks and could set safety risk in each work task in academic perspective. Also, TSMS has prevented death accident in practical perspective. And, the end-user of TSMS was construction manager, field Engineer, and labors, TSMS could mainly prevent safety accident while labors had performed in site.