It is said that there were two phases in the early stage of Islamic expansion to the East. One was those with military activities and conquests, as is seen in the areas like Central Asia, Afghanistan and Northern India. And the other was without any kind of military conquest but with trading activities and Sufi missionaries, as in Indian Ocean, South East Asia and Africa. On the details of the former, many researches have been done so far, but as for the latter, only little has been studied. In Malabar, southwest coastal area of India, and in Sri Lanka, two traditions concerning the coming of Islam have been recorded. The older one is of tenth century A. D. and the later one is of, probably, fifteenth century respectively. Analyzing the framework and the details of those two, present writer tries to illuminate the socio-economical circumstances of early Muslim community of these areas.