With the increasing demand for lightweight and high-stiffness structural materials in advanced manufacturing, aluminium matrix composites (AMCs) have attracted increasing attention because of their high specific strength, excellent thermal conductivity, and good workability. However, the relatively low elastic modulus of conventional aluminium alloys (typically approximately 70 GPa) limits their application in stiffness-critical fields. To overcome this drawback, researchers have explored various strategies to increase the elastic response of AMCs, including the incorporation of high-modulus reinforcements, interface engineering, and structural densification. This review systematically summarizes recent progress in improving the elastic modulus of AMCs, with a focus on the design of reinforcements (such as ceramic particles and carbon nanomaterials), interface control strategies (including load transfer efficiency and residual stress mitigation), microstructural optimization (in terms of particle size, alignment, and densification), and processing routes (such as powder metallurgy, melt processing, and additive manufacturing). Particular attention is given to the emerging role of multiscale synergistic reinforcements and structure-function integrated design, which provide new pathways for achieving simultaneous improvements in modulus, strength, and ductility. Finally, future directions are discussed, emphasizing the potential of modulus-oriented design strategies for next-generation AMCs in intelligent structural fields and extreme service environments.