This scientific monograph gives a detailed information about reproduction biology in thegrey wolf Canis lupusin Belarus. This topic includes the wolf breeding (mating and denning) behavior, fertility of the species and mortality of its pups. The initial material was notcollected occasionally from wolf hunters and wolf pup searchers, but mainly gained byauthors first-hand according to a well-set research design and long-term. By analyzing thegathered data, we became convinced that in the wolf reproduction biology there are moreexceptions than rules. Therefore, the standard patterns of reproduction biology in wolvesthat are wide-spread in the published literature about the species we call as common beliefsthat are given versus the wolf reality that we have found in Belarus. Concerning the non-standard features in the wolf reproduction biology, we revealed that multiple breeding inwolf pack is a common phenomenon, breeding of yearling females and wolf-doghybridization were found to be irrespective the food base and strongly depending on thespecies population density i.e. they are reproduction regulations. Wolf pup mortality wasinvestigated and the crucial role of deliberate predation of lynxes on wolf pups wasrevealed.