A control apparatus for an automatic transmission includes a control section (12a) having a target secondary pressure setting section (12c) configured to set a target secondary pressure (Pt sec) within a strength limit of the belt, and an operation switching section (P2,P3) configured to switch a shift operation from a normal speed to a high speed higher than the normal speed when a predetermined condition is satisfied. The control section (12a) is configured to control the secondary pressure regulating valve by a feedback control based on the target secondary pressure (Pt sec) and the actual secondary pressure (P sec) sensed by the hydraulic pressure sensor. The target secondary pressure setting section is configured to modify the target secondary pressure by adding a predetermined quantity when a correction initiation condition is satisfied, the condition initiation including a first condition that the shift operation is performed at a high speed by switching of the operation switching section.