This work aims to address fundamental feasibility of conducting hydrotreating reactions in structured catalyst channels in general and in ceramic monolithic catalyst modules in particular. CoMo/gamma-alumina hydrotreating catalysts made in the monolith structure form of channel size of about 1mm are tested with real-world refinery feedstock under steady-state reaction conditions within the range of typical hydrotreating process operations. The reaction performance of the same catalyst material in the monolith-structured form is compared to that in the trickle bed configuration of crushed particles and cylindrical catalysts. The exceptionally high HDS and HDN activity is observed in the structured catalyst channel. The reaction activity of the structured catalyst is a few times that of the trickle bed activity. Such a large degree of the activity enhancement obtained by changing the catalyst bed structure (not intrinsic catalyst material) is explained by more effective catalyst utilization in the confined reaction channels than in the random-packed trickle bed.