The Amazon river prawn Macrobrachium amazonicum is widely exploited by artisanal fisheries in the north and north-east of Brazil (Maciel & Valenti 2009). Currently, this species has important potential for aquaculture where it is indigenous (Moraes-Valenti & Valenti 2010; Marques & Moraes-Valenti 2012). A multidisciplinary and inter-institutional program to develop M. amazonicum farming technology has begun in Brazil, of which this study is a component. As freshwater prawn hatcheries are often far from the grow-out facilities that they service, defining optimum conditions to achieve maximum survival and condition of postlarvae and juveniles during transport are critically important. Transportation is a traumatic procedure that consists of a succession of adverse stimuli, including the capture of postlarvae, their transfer to transport containers, the transport itself, the transfer of the postlarvae from the containers to the rearing unit and the stocking procedure itself. These procedures are known to be a potential cause of high mortality, particularly if water quality deteriorates during transport. Despite this, transportation of freshwater prawns has been relatively neglected in scientific literature. The transport of postlarvae of the giant river prawn Macrobrachium rosenbergii is described by New (2002), and the study and practice of the transport of juveniles of this species in oxygenated bags and tanks were described by Valenti, Daniels, New and Correia (2010) and Valenti, New, Salin and Ye (2010). Early reports about the effect of M. rosenbergii transport density were published by Alias and Siraj (1988), Smith and Wannamaker (1983), Vadhyar, Nair, Singh and Joshi (1992) and Zimmermann (1998). More recently, specific studies on optimizing survival during the transport of juvenile M. rosenbergii have been reported by Coyle, Tidwell and Vanarnum (2001) and Coyle, Tidwell, Danaher, Yasharian and Bright (2006). However, no studies on the transport of juvenile M. amazonicum have been reported. Our paper describes an initial attempt to rectify this deficiency by studying the effect of transport density on transport survival and immediate (24 h) post-stocking survival.