t: Heavy metals are one of the most stable pollutants in aquatic ecosystems. Determining the concentration and origin of heavy metals plays an important role in designing management steps to control the environmental conditions of aquatic ecosystems . It is usually important to determine the origin of these pollutants due to the increased concentration of heavy metals around industrial and agricultural areas. The Zayandehrud River is one of the most important rivers in central Iran. So far, the capability of aquatic ecosystem core sediments ,as a natural archive (environmental archive), are not considered on contamination studies of the Zayandehrud River with the heavy metals Zayandehrud ,. However, such studies can determine the depositional history of pollutants (especially heavy metals) to aquatic ecosystems from different origins in sediments related to the last 150 years. In this study, core sediments sampled from three urban lakes of Zayandehrud margin (Zobahan Lake, Zarinshahr Beach Park Lake and Dizicheh Lake), in order to determine concentration, flux origin trends of heavy metals (Cadmium, Nickel, Lead and Zinc) in the last four decades.. Moreover, the relationship between physicochemical parameters of sediments and heavy metal concentrations was investigated in core sediments. The concentration of heavy metals was determined using an atomic absorption device. The results showed the concentration range of cadmium, nickel, lead and zinc metals in the range of 25.45 - 99.45 and 16.5 - 83.15, 2.6 - 5.8 and 0.1 – 4.15 , 37.05 - 88.2 and 26 - 77.75, 3.65 - 6.36 and 0.05 - 4.75 mg/kg in core sediments of the Zobahan Lake and Zarinshahr Beach Park Lake, respectively. The total concentration of heavy metals in core sediments of two lakes revealed non uniform trends with depth. Calculation of Pearson correlation coefficients between the measured concentration of heavy metals with physicochemical parameters showed significant positive correlation betwee nickel, zinc and lead , and with pH, calcium carbonate and aluminum content of the Zobahan Lake sediment samples. In the core sediments of Beach Park Lake, only nickel and zinc showed a significant positive correlation with aluminum, sand and clay. Cadmium also showed a significant positive correlation with the percentage of silt in the core sediments of both lakes. The calculation of Geo-accumulation Index (I geo ) showed moderate pollution of nickel in some layers of the studied core sediments among the studied metals. However, according to the Enrichment Factor (EF), some layers were placed in the enriched and highly enriched showed that, only the concentration of cadmium is higher than the Effects Range Low (ERL), in most layers. The results of the study indicated the dominant natural origin of the studied heavy metals, but in the case of cadmium, the contribution of anthropogenic origin has shown a significant increase. Simultaneous comparison of the heavy metal flux trends with climatological drought index(SPI) and hydrological drought index (SDI) of the area showed that pollution flux of heavy metals in sediments has increased during the wet years. However, based on the results of sequential extraction, their main origin is natural and various contribution of anthropogenic source has been obtained in different layers. Keywords: Heavy metals, Source identification, Core sediments, Pollution flux, Urban lakesof Zayandehrud River margin.