Project implementation plan is a blueprint that confirms project performance activities and specifies required man-hour, period and resource imput ratio. Various figures, the results of implementation plan, are predicted through estimation, and because of superiority of objectivity and repeatability, numerical formula-based estimation model is often used overseas. COCOMO model is the representative estimation model whose theories and formulas are publicized and it predicts the total man-hour required for software system development. This model is publicized in "Software Engineering Economics" written by Professor Barry Boehm of the U.S., and is the most widely applied numerical formula-based estimation model. This study is conducted to provide a series of methods that are optimal for KTDS environment by choosing COCOMO II model among various types of COCOMO models. In establishing implementation plan, COCOMO II model alone is not sufficient, it is necessary to link with and apply standard WBS system and standard man-hour. In establishing specific implementation plan, phased standard WBS system in order of the first phase of all the activities implemented in the project, Activity, Task, and Role, and the man-hour put into this should be distributed according to standard ratio from COCOMO II model's total man-hour. This study provides explainations by establishing standard WBS system and linking with COCOMO II model.