The lattice oxygen evolution reaction (LOER) must be taken into consideration in order to completely comprehend the mechanism of the water splitting reaction . The idea of an alternate approach to the traditional proton-coupled electron transfer (PCET), wherein molecular oxygen is created via the participation of metal oxide and/or perovskite lattice oxygen, was proposed in a few research about OER catalysts in the early 1970s to the 1980s. However, only in the last few years a more rigorous assessment of the lattice oxygen participation has been provided by different research groups . Recently, Hardin and coworkers investigated the participation of lattice hydroxide species in forming surface-adsorbed hydroperoxides for OER on LaNiO3, LaMnO3, and LaCoO3 catalyst . Generally, the participation of lattice oxygen on LSCO compound has been validated by H2 -TPR studies , XPS studies and isotope labelling together with the differential electrochemical mass spectrometry (DEMS) method . In a completely new approach, we are reporting RRDE to validate this phenomenon. Mostly, RRDE technique is used to calculate the number of electrons transferred in the oxygen reduction reaction (ORR). However, this technique is explored for the first time in literature to understand the involvement of LSCO's lattice oxygen in OER and methanol assisted OER. Experimental data clearly proves that RRDE accurately monitors the lattice oxygen participation in the perovskite. Although, its explicit effect on catalysis is not obvious.