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The Sumatran Fault stretches for 1,900 km, The 1900 km long dextral slip fault, the Great Sumatran Fault (GSF), accommodates a significant amount of the trench-parallel component of the oblique convergence between the Indo-Australian and Eurasian plates. The Sumatran fault, unlike other great transcurrent faults, is highly segmented. The largest irregularity in GSF is observed in the central part of GSF (around the equator) where the fault splits into two sub-parallel strands up to 35 km apart; named it equatorial bifurcation and is a region that has a high level of seismicity. This research was conducted with the aim to obtain the profile of the shear wave velocity (Vs) based on the results of the Rayleigh wave dispersion curve inversion. In general, the research are divided into four main stages; standard data processing, cross correlation and stacking, initial velocity model analysis, dispersion curve analysis, and direct inversion. Empirical Green’s Function is obtained from the cross correlation results of each pair of stations from the temporary seismic network around the location. The preliminary results show that based on the analysis of the EGF dispersive signal’s seismicity of the station pair oriented relatively northwest – southeast and northeast - southwest, obtained the dominant distribution of noise sources related to oceanic activity on the coast of the Indian ocean, in the 5 – 20 s range. In that periods range, the average group velocity varies from 2-4 km/s. The apparent anomaly is thought to be due to the bifurcation in the region.