This paper investigates the influence of subjective task-load on perceived anthropomorphism dimensions within a cooperative pick-and-place task. Two different robot mounting configurations are chosen, which are assumed to differ with respect to motor interference, thus, leading to different levels of task-load. Results show significant dependencies of the anthropomorphism and animacy sub-scales of Godspeed and HRIES tests on several NASA-TLX dimensions, whereas positive changes of anthropomorphism dimensions are associated with increased task-load. It is known, that the level of anthropomorphism influences performance and user experience parameters during human-robot cooperative tasks. So, the investigated effect might increase the gap between robot capabilities and user expectations due to over-humanization and should be considered in cooperative action planning.