Marine sponges contain unique chemical compounds that are potential to be developed as new drugs. This study aimed to screen and characterize bioactive compounds of sponges obtained from Samalona Island, South Sulawesi. The sponges were extracted with methanol and partitioned with chloroform-water mixture. The bioactivity of sponge extracts was tested against Artemia salina Leach. Extracts that showed high bioactivity/cytotoxicity were fractionated using vacuum liquid chromatography and isolated using preparative thin layer chromatography. The obtained isolates were then tested against A. Salina. The isolated compound with highest bioactivity was characterized using UV light (chemical reactions and spectrophotometer UV and IR. Three out of 15 sponges collected yielded a highly toxic extracts against A. salina and the most active chloroform extract was obtained from Penares sp. sponge. Fractionation and isolation of the Penares sp extract generated an isolate with high toxicity with LC50of 0,0971 μg/ml. Characterization of the isolate showed no detectable bandunder UV light 254 and 366 nm and exhibited positive reaction with Dragendorff’s reagent. The UV spectra showed the maximum absorbance of the compound was 206 nm. The IR spectra showed that the compound contains amine (-NH), carbonyl (C=O), alkyl (CH3,-CH2, -CH-) and alkena (=CH) groups. In conclusion, Penares sp. obtained from Samalona island contains highly cytotoxic isolate that is potential to be developed as anticancer agent.