With the explosive surge in the volume of aid, skepticism towards aid effectiveness has been emerging as a major issue among donor countries. In particular, as aid increased on a diverse and vast scale, aid fragmentation became serious, which led to a decline in quality of aids. However, aid fragmentation does not necessarily cause a decrease in aid effectiveness, for aid fragmentation refers to an increase in quantitative aid by various participants. Thus, this increased amount of aid can rather help the development of recipient country's economic growth under certain conditions. Based on these conflicting research results, this study analyzed how aid fragmentation affects the effectiveness of aid depending on the level of economic development in recipient countries. In addition, the path of causal relation between the level of economic growth and aid fragmentation was identified. To this end, this study discussed the impact of such a strategic choice on aid effectiveness, especially focusing on changes in fiscal spending among the policy strategies of recipient countries. Through this, the effect of the aid fragmentation on aid effectiveness in Southeast Asia and sub-Sahara Africa, where economic levels are significantly different, was analyzed, and the mediation effect of changes in fiscal spending was reviewed. As a result, Southeast Asia has shown no significant impact on aid effectiveness, while sub-Saharan regions had positive impact. In the case of sub-Saharan regions, it was also shown that changes in fiscal expenditure had effect of curbing the aid effectiveness. Therefore, it can be said that proper level of aid fragmentation can contribute to enhancing the effectiveness of aid, but it could also lead to a reduction in the effectiveness of aid due to problems such as the distortion of government's fiscal expenditure and the inability of government carrying out the intended aid projects.