A new metallohybrid silsesquioxane (S) was synthesized herein from copper and ferricyanide via a cyanide bridge to produce a new electroactive hybrid material (SCuH), which was then characterized by spectroscopic and microscopic techniques and cyclic voltammetry. The voltammetric behavior of SCuH employing a graphite paste electrode indicates a well‐defined redox couple with formal potential Eθ′=0.76±0.01 V. The electrode exhibited high sensitivity to nitrite and was successfully tested for nitrite detection. The linearity of the analytical curve was 2.0×10−4 mol L−1 − 1.0×10−3 mol L−1, with a limit of detection of 2.65×10−5 mol L−1, and sensitivity amperometric value of 57.63 mA/mol L−1. These findings suggest that this material displays exceptional potential for application in electrochemical sensors designed for nitrite detection.