There is not any information on the time series, type and density of the Blue Crab post larvae (megalopae) settlement in the Mediterranean Basin in Turkey. This study aims to uncover the settlement time, area and amount of the Blue Crab post-larvae in the north shore of Yumurtahk Cove (northwestern of Iskenderun Bay) and to define the relations between post-larvae settlement and ecological factors like temperature, salinity, moon phases. In the Yumurtahk Cove, post-larvae samples were collected every other day on standard artificial collectors during June-November 2011 at the 4 stations which have different bottom structures. At the end of study 28 Callinectes sapidus, 218 Portunus sp. and 8 from other species of the Portunidae family post-larvae were caught. 54% of the total number of blue crab post-larvae settled on sea grass beds, 25% on marhes and muddy bottoms, 14% on sandy and grassy areas and 7% on sandy bottom areas. Settlement occurred between mid-June and mid-October. The densest settlement was recorded in August and September (86%). Largest settlement peak occurred at the time of the full moon and major settlement peak on a single sampling date was detected on the 19th of July (full moon) and 29th of August (new moon). In this study, at least some very important information on the post-larval stage one of the most important life stages-of the Blue Crab population in our region has been obtained for the first time.