Conductive diamond electrode has been studied for electrocatalytic of luminol to generate chemiluminescence, which is famous as electrochemiluminescence (ECL) as it is generated from a redox reaction by applying a potential on the electrode surface. The diamond electrode is established in electrochemical sensors due to its unique properties, including its significantly broad potential window and very low capacitance. In addition, it has high resistance in extreme potential applications, which is often required to provide the oxidation reduction of the reactant or co-reactants. The electrode was prepared by replacing the carbon film in a screen-printed carbon electrode (DropSens 150, Methrom) with a piece of boron-doped diamond (BDD) film (d = 0.3 cm2) to form a screen-printed BDD electrode (SPE-BDD). The ECL signals were measured in a dark box with a photomultiplier tube (PMT) set at 800 mV as the detector. During the ECL measurements the voltammetry was applied at BDD electrodes in a phosphate buffer solution at an optimum pH 9 containing 10 mM luminol with the presence of varied concentrations of co-reactant and the target samples. The presence of peroxide is proven to enhance the ECL signals of luminol, while the presence of hypochlorite and metals  causes the decrease of the luminol ECL signals. Accordingly, the applications in peroxide, hypochlorite, and chromium sensors was demonstrated. Comparison to other typical detection using electrochemical and electrochemiluminescence techniques indicated that the developed method has a potency to develop other types of chemical sensors.