In this paper the applicability of stochastic finite element method to the in-service reliability analysis of offshore jackets is discussed. The methodology basically involves the formulation sensitivity matrix of the structure using conventional stiffness matrix based on mean values and the variations. The Taylor Series Expansion Technique is used, which involves the single inversion of a large matrix in order to evaluate all sensitivities. It has been shown that this methodology is computationally less taxing than Monte-Carlo Simulation, which involves numerous repetitions of conventional structural analysis involving inverses of large matrices. An existing offshore jacket of 100m length is taken as a vehicle for the illustration of this methodology.