<p>With rapid development of 5G communication technologies, a variety of electromagnetic interference (EMI) shielding materials have been developed to protect against detrimental electromagnetic radiation. However, these materials often face fundamental challenge of balancing high EMI shielding effectiveness (SE) and low electromagnetic wave reflection. Herein, an architecture featuring a porous substrate and gradient conductive structure is constructed using cellulose aerogel as template and MXene as functional filler. MXene nanoplates are controlled to adhere to the cell walls of the cellulose porous template with a gradient distribution. This gradient distribution forms an efficient electromagnetic wave absorption network. The low concentration side provides a good impedance match between air and the surface, allowing the incoming of most microwaves. As the microwaves propagate along the positive conductive direction, the adsorption ability continues arise and the high concentration end provides highly reflection ability to prevent the escape of microwaves. Consequently, this porous structure combined with gradient conductivity results in a “low reflection–absorption–reflection–reabsorption” process for the electromagnetic waves. This leads to a high EMI SE of 31.2&#xa0;dB in the frequency range of 8.2–12.4&#xa0;GHz and a high absorption coefficient (A) of 0.84. Of more practical significance is the investigation of the relationship between the distribution state of MXene nanosheets and the corresponding EMI shielding performance, which highlights the advantages of porous architecture and conductive gradient structure on simultaneously achieving high EMI SE and high A.</p> Graphical abstract <p></p>