Polycyclic aromatic hydrocarbons (PAHs) are known as persistent pollutants in marine ecosystem which, originate from several sources and cause many problems for both aquatic organisms and human. The study of PAHs compounds ratio in bivalves can help to determine their source and rout of input in to the sea and such information can be used in fisheries and environmental management. Since oil related industries are well developed in Bushehr coastal waters this area is supposed to be impacted by PAHs. This study was carried out to determine the concentration of PAHs and their source in ark clams (Barbatia helblingii) along Bushehr shoreline. Samples of ark clams (Barbatia helblingii) were collected from five different stations. 30 numbers of clams in same size (mean: 35mm) were collected from each station.  They were dissected and their soft tissues were digested in methanol. PAHs content of the samples was extracted by hexane and analyzed using HPLC. Result showed that tPAHs concentration in clams ranged from 125.5 to 634.7 ng g^-1(dw). Significant difference was observed between tPAHs concentration in clams belonged to different stations (P<0.05). The maximum and the minimum concentrations of PAHs were measured in clams collected from stations Rafael and Abshirinkon respectively. Results obtained from some relative ratios of single PAHs compounds indicated that Bushsher shore line receives PAHs from both pyrolytic and petrogenic origins. Due to low PAHs concentration and bioavailability in station Abshirinkon, It Appears that this site is suitable place to establish aquaculture fields. The mean concentration of tPAHs in B.helblingii was 421.6 ng g^-1which was notably higher than what reported form some other bivalve species from other parts of the world, which is indication of high bioavailability of PAHs. Due to adverse effects of PAHs on human and aquatic life, study of PAHs in edible fishes is necessary.