The fastness properties of the flower of Thespesia populnea dyed silk fabric have been studied using different combination (1:3,1:1 and 3:1) of various mordants, such as myrobolan:nickel sulphate, myrobolan: aluminium sulphate, myrobolan: potassium dichromate, myrobolan: ferrous sulphate and myrobolan:stannous chloride. The wash, rub, light and perspiration fastness of the dyed samples have been evaluated. Comparing thefastness properties and colour strength of flower of Thespesia populnea dyed silk by using combination of mordants. In the comparative study of fastness properties and colour strength of the dyed silk samples Thespesia populnea in simultaneous mordanting method with 1 : 3 mordant combination gives better results.