The paper presents the experimental program developed in the Laboratory of Civil Engineering Faculty of the ”Politehnica” University of Timi oara, Romania, in order to establish the real behavior of bolted connections in cold formed steel trusses. First, the semi-rigid behavior of cold formed steel truss joints is demonstrated by means of test of typical T joints. A formula for the axial rigidity of single lap joint is determined, and, based on this formula, theoretical models are proposed for the rotational rigidity of cold formed steel truss bolted joints. In the third step of the experimental program, a cold formed steel truss is tested, in order to observe the structural behavior of joints and to validate the theoretical assumptions. A numerical analysis of the tested structure is also performed, and comparisons with the experimental results are given.