An integrated circuit device includes: a first fin-type active region in a first area of a substrate, the first fin-type active region having a first recess filled with a first source/drain region; a first device isolation layer covering both lower sidewalls of the first fin-type active region; a second fin-type active region in a second area of the substrate, the second fin-type active region having a second recess filled with a second source/drain region; a second device isolation layer covering both lower sidewalls of the second fin-type active region; and a fin insulating spacer on the first device isolation layer, the fin insulating spacer covering a sidewall of the first fin-type active region under the first source/drain region.