Hierarchically porous materials have attracted significant attention due to their potential in energy conversion and storage, catalysis, photocatalysis, adsorption, separation, and life sciences. This review discusses the synthesis strategies and structure design of hierarchically porous materials. The hierarchy of porosity, structural, morphological, and component levels is crucial for achieving high performance in various applications. A wide range of synthesis methods have been developed, including templating methods (surfactant templating, nanocasting, macroporous polymer templating, colloidal crystal templating, and bioinspired processes), conventional techniques (supercritical fluids, emulsion, freeze-drying, breath figures, selective leaching, phase separation, zeolitization, and replication), and basic methods (sol-gel controlling and post-treatment), as well as self-formation phenomena. The review highlights the synthesis of hierarchically porous structures with various chemical compositions, such as dual porosities (micro-micropores, micro-mesopores, micro-macropores, meso-mesopores, meso-macropores) and multiple porosities (micro-meso-macropores and meso-meso-macropores). The review also discusses the applications of hierarchically porous materials in catalysis, adsorption, separation, sensors, energy, and life sciences. The synthesis strategies include surfactant templating, replication, sol-gel controlling, and post-treatment. The review emphasizes the importance of controlling the hierarchy at different levels to achieve desired functionalities and performances. The review provides a comprehensive overview of the synthesis methods and their corresponding morphologies, porous structures, and chemical compositions. The review aims to help researchers entering the field and those working in the field to quickly access helpful reference information about the synthesis of hierarchically porous materials and methods to control their structure and morphology.Hierarchically porous materials have attracted significant attention due to their potential in energy conversion and storage, catalysis, photocatalysis, adsorption, separation, and life sciences. This review discusses the synthesis strategies and structure design of hierarchically porous materials. The hierarchy of porosity, structural, morphological, and component levels is crucial for achieving high performance in various applications. A wide range of synthesis methods have been developed, including templating methods (surfactant templating, nanocasting, macroporous polymer templating, colloidal crystal templating, and bioinspired processes), conventional techniques (supercritical fluids, emulsion, freeze-drying, breath figures, selective leaching, phase separation, zeolitization, and replication), and basic methods (sol-gel controlling and post-treatment), as well as self-formation phenomena. The review highlights the synthesis of hierarchically porous structures with various chemical compositions, such as dual porosities (micro-micropores, micro-mesopores, micro-macropores, meso-mesopores, meso-macropores) and multiple porosities (micro-meso-macropores and meso-meso-macropores). The review also discusses the applications of hierarchically porous materials in catalysis, adsorption, separation, sensors, energy, and life sciences. The synthesis strategies include surfactant templating, replication, sol-gel controlling, and post-treatment. The review emphasizes the importance of controlling the hierarchy at different levels to achieve desired functionalities and performances. The review provides a comprehensive overview of the synthesis methods and their corresponding morphologies, porous structures, and chemical compositions. The review aims to help researchers entering the field and those working in the field to quickly access helpful reference information about the synthesis of hierarchically porous materials and methods to control their structure and morphology.