Among marine invertebrates, mollusc is one of the potential source of bioactive substances. The number of natural products isolated from marine organisms increases rapidly and now exceeds. The antimicrobial research is geared towards the discovery and development of novel antibacterial and antifungal agents. In the present study a total of 4 extracts from Cypraea arabica was assayed for its antimicrobial activity against ten bacterial and six fungal pathogens. Among all the four fractions fraction 3 (Benzene : Methanol) showed maximum level of inhibition zone 18mm against Salmonella typhi. The results of maximum inhibitory concentration revealed that among the concentrations, 100mg/ml concentration showed maximum activity and 1mg/ml concentration showed minimum activity. Crude methanol extract showed only negligible activity whereas column fractionated extracts showed significant antifungal activities. F3 fraction of Cypraea arabica developed maximum zone of inhibition (14mm) against Candida albicans.