The objective of the present paper is to study the factors associated with environmental bilateral aid to recipient countries over the 1990-2013 period, to assess whether it is motivated by non-environmental factors such as donors’ self-interest. Environmental ODA is measured using the AidData’s Core Research Release, Version 3.1. Three kinds of variables that might influence environmental aid allocation are considered: the environmental and non-environmental needs and merits of recipient countries, and the economic and political interests of donors. Environmental needs and merits variables include vulnerability to extreme climate events and the stringency of climate policy. The Poisson and Fractional regressions find that while vulnerability to climate change seems to be a key determinant of environmental aid, its allocation is poorly linked to recipients’ climate mitigation policies. We also find weak evidence of association between donors’ interest variables and environmental aid on average, exception made for trade. But a donor-by-donor analysis allows to get deep dive into all the relations above and unveils that some donors are more sensitive to environmental variables, while others rather seem focused on their economic and political interests.