Simeulue Island is located in the forearc west of Sumatra Island. Due to the subduction process of the Indo-Australian plate beneath the Eurasian plate, high seismic activities occur around Simeulue Island. A temporary seismic network was installed on the island from December 2005 to March 2006 to study seismicity around this region. From previous studies, using ambient vibration records, it is possible to extract a site amplification of sediment on the top of a bedrock, which gives influence on the seismic signal. In addition to the site amplification, it is also possible to determine information of the velocity model on the shallow subsurface. In this preliminary study, we applied horizontal to vertical time frequency analysis (HVTFA) to obtain ellipticity from recorded vibration from three temporary seismometers. An inversion was applied to the computed Rayleigh ellipticity to obtain the best fit subsurface velocity model.