Recently, immune memory in invertebrates has been demonstrated, revealing an improved immune response to pathogen challenge after previous nonlethal exposures to the pathogen or its analogues. However, this mechanism has been understudied in freshwater crayfish. Therefore, in this study the effects of immune priming on the noble crayfish, Astacus astacus were explored. Noble crayfish were primed with: i) crayfish saline solution, ii) beta-laminarin, iii) inactivated Aphanomyces astaci hyphal suspensions and iv) inactivated A. astaci zoospores. Then, the survival, and immediate and prolonged changes were monitored in the following immunological parameters: total hemocyte count (THC), differential hemocyte count (DHC), total protein content and gene expression of prophenoloxidase, immune system activator C/EBP and immune system repressor Kr-h1. Hemolymph sampling was conducted 1, 4, 8, 24 hours and 16 days post-priming. Additionally, it was tested if priming could induce A. astaci resistance as a long-term effect. The results indicate that immune priming has no effect on the survival of the noble crayfish. Furthermore, the changes in the monitored immune parameters of the noble crayfish are immediate and mostly return to normal values within 24 h. Finally, results on the resistance to A. astaci remain inconclusive as no mortality due to infection was observed.