Nigeria had over the years faced skyscraping level of corruption and political instability. Hence, Corruption and political instability are undoubtedly one of the greatest challenges in Nigeria as these challenges that are not only leading to impoverishment and loss of lives, but also threatening the stability of the country. This made it imperative to examine the contributions of corruption and political instability on infrastructural decay in Nigeria. The study used secondary data. Data on Infrastructural Development Index (IDI) was used as proxy for infrastructural decay in Nigeria which is the dependent variable; while data on corruption perception index (CPI) and political instability Index (PII) were the independent variables. It employed Error correction model to relate co-integrated variables in the short run. The study revealed that corruption had negative impact on infrastructural development index in Nigeria within the study period. This implied that increase in corruption led to increase in infrastructural decay in Nigeria. The study revealed that political instability resulted to high infrastructural decay in Nigeria within the study period. This means the higher the level of political instability, the higher the level of infrastructural decay in Nigeria. The study recommended that government should ensure that the level of corruption is reduced to the barest minimum level in order to attain the desired level of infrastructural development to reduce infrastructural decay in Nigeria. Finally, government should employ tactical strategies to reduce political instability so as to boost infrastructural development towards curtailing infrastructural decay in Nigeria. Key Words: Corruption, Political, Instability, Infrastructural Decay, Development.