It has been largely assumed that the mendicant friars, particularly Franciscans, had a tradition of the study of natural philosophy, since a good number of medieval scholars interested in this discipline were Franciscan friars. However, some historical facts render such an assumption invalid. Concentrating on the thirteenth and early fourteenth centuries, this paper investigates whether the interest of some of the Franciscans in natural philosophy can be accounted to the whole Order, and whether there was a deliberate policy of the Order imposed through the constitutions. The examination of the evidence points to the conclusion that the Franciscan attraction to natural philosophy was limited to the masters in Paris and Oxford who, in the main, were trained in arts prior to their entry into the order, and that their involvement in natural philosophy was an extension of the general interest present in these two main university towns.