We study the role of food price rising and income generating assets as determinants of household food insecurity among the extreme poor in rural Bangladesh for the period 2002-2011. We do so in the context of an anti-poverty program, targeting the ultra-poor (TUP), which transferred productive livestock assets to the very poor. We find a positive significant impact of the asset transfers on household’s food security irrespective of whether we use subjective or objective measures of food security. Most importantly we find that the long-term impact of the program (estimated over 2002-2011) is smaller compared to mid-term (2002-2008) and short-term (2002-2005) impacts for all the indicators. We test whether this declining program impact is driven by the steep rise in food prices in the post-2007 period. We find that in the pre-crisis period participant households benefited while in the post crisis period they affected negatively by the price shock. This result explains the declining effect of TUP program. Our analysis therefore illustrates how the external shocks can undermine the effectiveness of an otherwise well-functioning anti-poverty program.