Provided is an elastic circular knitted fabric which exhibits good wear comfort and excellent movement follow-up ability and can contribute to improvement in motor functions, which exhibits little tightness or a reduced shift during an action, which is not limited in application by stretching force, which is useful as a clothing material that is not susceptible to loosing shape due to wearing, and which has both excellent elongation and excellent elongation recovery of elongation. An elastic circular knitted fabric composed of an elastic fiber and a nonelastic fiber, wherein: knitted loops which contain the elastic fiber are continuously connected in the warp direction of the knitted fabric; the wales of the knitted loops are arranged in the weft direction of the knitted fabric in such a state that at least one wale of the knitted loops is present for every two wales; the aperture angle between the fiber bundles constituting the knitted loop of the nonelectric fiber is 50 to 150 degrees; the stretching forces of the elastic circular knitted fabric in the warp and weft directions at 80% elongation are 100 to 800 cN; the ratio of the stretching force in the warp direction to that in the weft direction is 0.5 to 1.8; and the elongation recovery percentages of elongation in the warp and weft directions are 85% or more as determined after subjecting the fabric to three 80% elongation/recovery cycles.