The detection of extracellular vesicles, or exosomes are important mediators in intercellular communication and often play a role in cancer progression. CD63 is a key exosomal protein due to its distinctive cellular functions and association with many cancers. This describes a label-free electrochemiluminescence (ECL) nanoimmunosensor for the detection of CD63 protein over mesoporous carbon screen-printed electrode (MC-SPE) modified with novel nanocomposite of carbon nanochips (CNCs), iron oxide (Fe3O4) and nafion (NAF). Fourier-transform infrared spectroscopy and field emission scanning electron microscopy were used to analyse nanocomposite. All the analytical performance of fabricated CD63 immunosensor were conducted applying ECL. In spite of the simple fabrication strategies utilized, the fabricated immunosensor showcased a broad linear range to detect CD63 from 100 fg mL−1 to 10 ng mL−1, with a limit of detection of 100 fg mL−1, excellent selectivity, interference-resistance capability and potential to detect CD63 in real clinical samples.