The residential sector of Algeria consumes 29% of the total energy consumption. In order to reduce and address this consumption along with the challenges of climate change, the Algerian public policy considers energy efficiency investment measures (EEIMs) in the residential sector as a key factor. However, despite the recommendations and incitement measures from the government, the adoption of EEIMs of Algerian homeowners is too low. In 2018, EEIMs have been implemented in 4,000 houses. This number represents only 4% of the government's target which is the implementation of EEIMs in 100,000 houses per year. The present article, accordingly, attempts to explore the barriers to the adoption of EEIMs. To this effect, a questionnaire survey with 150 randomly selected Algerian single-family homeowners in Mostaganem area was used for the study. It was found that the five greatest barriers to the adoption of EEIMs were: (1) the lack of subsidies and rebates on energy efficient equipment, (2) the high initial prices of energy efficient equipment, (3) the lack of techniques and tools for the estimation of saved energy, (4) the unwillingness to borrow money and (5) the difficulty of identifying, procuring, installing, operating and maintaining energy efficiency measures. The principal component analysis categorised 16 barriers around four components: (1) "Financial" barriers, (2) "Technological" barriers, (3) "Lack of time and knowledge" barriers and (4) "Attitude towards energy efficiency improvements" barriers. Finally, the multivariate analysis of variance (MANOVA) analysis has shown that the perception of barriers to the adoption of EEIMs also differs in accordance with certain personal characteristics of the homeowner.