Flow of internal mobility behavior occurs to different scale, types of stream and also through distance migration in West Bengal. Provincial and flow of intra-inter district and interstate migration and huge influx of migration streaming (rural-rural, rural-urban, urban-rural and urban-urban). Data is taken from census of India (2001) D-13: Migrants by place of last residence by duration of residence (duration of 0- 9 years) has been used to study the flow of in-migration and out-migration in West Bengal and methodology has been used estimation of total migrant population in each district is calculated through the matrix formation. Intra-district migrant sex ratio is favorable to females in all the district of West Bengal. Inter district in and out migrant sex ratio skewed in favour of female in districts like Hugly and Inter district out migration lowest from Kolkata district and Interstate in migration sex ratio is very low in all the district of West Bengal. Huge numbers of males are coming from the Eastern region of bordering states (like Jharkhand, Bihar, Orissa and Assam) to different districts of West Bengal.