This study presents an electrochemical sensor for sensitive detection of nitroaromatic compounds using a three‐dimensional (3D) porous graphene with polyoxypropylene supported reduced graphene oxide (PEA‐RGO) and embedded β‐cyclodextrins (β‐CD). First, PEA‐RGO was synthesized by the condensation reaction between graphene oxide (GO) and amino‐terminated polyoxypropylene (PEA), followed by hydrazine hydrate reduction. Then, β‐CD was embedded into the porous of the above 3D graphene to obtain PEA‐RGO/β‐CD nanohybrid. Various characterization techniques, such as microscopy imaging, infrared spectrometry, thermal analysis and electrochemical measurements, were employed to confirm the successful synthesis and unique 3D architecture structure of PEA‐RGO/β‐CD. Afterwards