In developing countries, most women are suffering from endometriosis disease and unfortunately, there is not yet an efficient and adaptable biomarker that could be explored further for the diagnostics of endometriosis. In this direction, we are proposing interleukin-10 (IL-10) as a better biomarker and its efficient electrochemical immunosensing at an ultra-low level for the diagnosis of endometriosis based on demonstrated high sensitivity and specificity. To develop the proposed sensing platform, a glassy carbon electrode (GCE) was electrochemically modified with gold nanoparticles (AuNPs) utilizing the chronoamperometric method. Further, the Au/GCE platform was functionalized using a cysteamine-self-assemble monolayer through glutaraldehyde to achieve successful immobilization of the monoclonal IL-10 antibody and selective detection of IL-10 in real samples as well. The interaction between monoclonal IL-10 antibody and IL-10 antigen was studied using square wave voltammetry (SWV) technique. The cysteamine-based immunosensor displayed a dynamic range from 1 atto gram (ag i.e., 10^-18 g) to 5 pico gram (pg i.e., 10^-6 g) per mL, and the lower detection limit of 0.33 ag per mL of IL-10 was obtained. The validation of achieved sensing performance was evaluated by comparing all the parameters regarding the Enzyme-linked immunosorbent assays (ELISA). Additionally, the developed sensing platform exhibits high sensitivity, specificity, and reproducibility together with high stability and provides an effective appose to detect IL-10 cost and time-effective compared to ELISA. Thus, such AuNPs-based IL-10 sensing platforms of high-performance features can be promoted as an efficient analytical tool for clinical application to support women's healthcare globally.