Diet has a profound impact on the relationship between body mass and reproductive strategy in mammals, and the implications have been of particular interest in recent years. Previous studies have indicated that diet strongly shapes the way that body mass drives reproductive strategy in herbivores and omnivores, but not in carnivores. One suggested explanation for this result is that the differences in resource distribution between invertebrate feeding carnivores (hypocarnivores) and vertebrate feeding carnivores (hypercarnivores) combine to produce a non-significant result when they are analysed as a single unit. In this study, we investigate how dietary and locomotor differences in carnivores influence the relationship between body mass and reproductive strategy within the context of phylogeny, using a reproductive strategy index and performing a phylogenetically informed analysis of covariance (PANCOVA) on 101 evolutionary trees. We examine this question in two distinct ways. First, we separate carnivores by diet (hypocarnivores, mesocarnivores, and hypercarnivores). Second, we separate carnivores based on their mode of locomotion to determine how ecology may affect this relationship irrespective of diet. For all diet categories we find that the effect of diet is significant when taken individually but is not significant with p>0.05 when carnivores are investigated as a single unit. When examining locomotion categories individually, we find that statistically significant trends exist for all groups but volant carnivores. When analysed as a single unit the effect is significant with p<0.05. These results suggest future work should investigate ecological differences to understand the variation in reproductive strategies among carnivores. In the end, the aspects of diet investigated here do not influence the relationship between body mass and reproductive strategy in carnivorous mammals, while ecology does. This suggests that evolution in carnivore reproductive strategy is driven by distinctly different factors than those in omnivorous or herbivorous mammals.