This research aim is to get a reasonable labyrinth planning method and to apply this method a new labyrinth project and to remodel a constructed labyrinth though to analize quantitively a protecting effect for gamma-ray by using labyrinth passage of a hot cell and to chart a calculation method for the protecting effect. The main points of this paper are the following: 1. Analizing and simplifing the effect of scattering of gamma-ray on the walls in a labyrinth. 2. Summing up a evaluation method and data of the labyrinth effects and to get the simple chart to it for easy checking after the preliminary calculation. 3. Showing a practical calculation and application to make a planning of a labyrinth passage on a new hot cell project or to make a remodeling of a constructed labyrinth passage on a used hot cell by the calculation sheet.
