An adjustable deforming composite structure based on a hydrogen-induced expansion effect and a preparation method therefor are provided. The hydrogen-induced expansion effect means metals absorb hydrogen under a hydrogen-containing atmosphere and at a temperature to produce a volume expansion effect. Reactions between the metals and hydrogen are reversible reactions. When a hydrogen partial pressure is reduced or the temperature is increased, the hydrogen in the metals is removed, and the metals are restored to an original shape. Under a stimulation of external hydrogen and heat, a composite of a hydrogen-absorbing metal and other non-hydrogen-absorbing materials undergo an adjustable deformation according to a design, and a material undergoes reversible shape changes. The preparation method is applied to composite materials for a 4D printing and is used for an intelligent shape adjustment at a medium to high temperature.