A　long-term　investigation　on　energy　consumption　was　carried　out　for　13　residential　buildings　in　Tohoku　area　since　Nov.　2002.　In　order　to　make　clear　the　effect　of　low-impact　lifestyle　on　energy　consumption,　the　lifestyle　menu　was　indicated　to　the　occupants　in　10　residential　buildings,　and　the　actions　following　the　menu　was　investigated.　In　addition　to　energy　consumption　reported　in　the　previous　paper,　CO2　emissions　reduction　effect　by　the　lifestyle　menu　was　analyzed　during　a　week　when　the　low-impact　lifestyle　was　acted.　As　a　result,　CO2　emissions　of　the　some　investigated　houses　were　not　necessarily　reduced　even　though　the　energy　comsumptions　were　saved　by　the　actions　following　the　low-impact　lifestyle　menu.　It　is　important　to　lead　energy　saving　by　low-impact　lifestyles　to　CO2　emissions　reduction　aswell.