In the decay of turbulence generated by passing through Sierpinski tetrahedron, there exists a region in accordance with the exponetial law, without obeying the power law. In this study, mechanism of exponential decay is investigated by measuring the profile of velocity statistics over the cross section. Mean velocity profiles are similar to each other amongst the structures with different number of iteration (N=2, 3, 4) and so are turbulence intensities except the case for the least number (N=2).