Retarded foam gel for profile modification of oil field

The invention concretely provides a retarded foam gel for profile modification of oil field. The retarded foam gel is characterized in that the foam gel comprises the following compositions in percent by weight: 0.1-0.3 wt% of a thickening agent, 0.01-0.03 wt% of a cross-linking agent A, 0.1-0.3 wt% of a cross-linking agent B, 0.2-3.0 wt% of an auxiliary agent, 0.6-9.0 wt% of a gas generation agent, and 87.37-98.99 wt% of water. The foam gel is easily-available in raw material and simple in technology, and solves the problems that a conventional foam profile modifier is large in viscosity, large in friction and not easy to inject during injection, and after the foam profile modifier is crosslinked, viscosity loss is severe and the half life is short. The retarded foam gel is good in salt resistance and temperature resistance, and possesses wide application prospect.