This paper investigates the cultural adaptation of loan words in Mosuli Arabic from a sociolinguistic perspective. It aims at investigating the extent of the sociolinguistic factors, namely: age, gender, social class and educational attainment, influence on loan words usage in Mosuli speech community and also investigating the effect of the environmental factor, in terms of the surrounding regional effect, on Mosuli Arabic. It is hypothesised that the sociolinguistic factors have influence on the rate of loan words usage in that community and that the environmental factor has influential effect in entering loan words into it. To achieve all these, a sociolinguistic modified model is adopted which is based on a theoretical framework, namely: Poplack et al (1988). Informal interviews are conducted with forty-eight native Mosuli speakers divided equally according to sociolinguistic factors (namely: age, gender, social class and educational level) to calculate the rate of loan words used by each subgroup and, then, analysed in the light of the adopted model. This study finds that the sociolinguistic factors affect loan words usage in Mosuli Arabic. Although Mosuli speech community has a shared strategy for incorporating loan words into Mosuli Arabic discourse and that there is a uniform pool of loan words in Mosuli speech community and each speaker chooses from this pool, there is a slight tendency for one subgroup to use loan words rather than its counterpart. It is observed that female, old age, low class and illiterate groups incline to use loan words rather than their counterparts.