<p>The Rainbow trout (Oncorhynchus mykiss) is the most used kind with purposes piscicolas in the cold continental waters of Colombia. At the moment in Boyaca’s Department there are few studies related to its hematological parameters. In consequence, finding the blood normal values of this type of trout represents for the systems of production acuicola the possibility of reaching the standars of production and productivity of these models of cattle exploitation. As a result of this study, our objective is to standardize the cellular values of de blood of the rainbow trout in conditions of altitude. In this sense we calculate each one of the parameters wich shapes the eritrogram, leucogram, and trombogram in the healthy fish, in order to accede to absolute results and to shape the values of reference on which the clinical or the truchicultor can support to, identify the presence of unfavorable conditions for the health of the rainbow trout and a clinical criterion for the indication of treatments.</p>