The occurrence of SARS-CoV-2 infection since 2019 created a havoc worldwide. To add to this, the appearance of various variants from all parts of the world increased the pandemic and transmission capacity of the virus. Since proteins play the final role during the entry, replication as well as exit events, it becomes necessary to understand changes that might have taken place in all the protein constituents of the virus when it is inside the host. Present study was undertaken to look for the various protein components of the virus that is detectable in the host cell and its comparative existence in different variants of SARS-COV-2. The electrophoresis of the virus samples isolated from Vero cell lines were performed and then subjected for LC-Mass Spectrometric analysis. It was observed that Spike protein was the major protein visible in the Delta strain quantitatively compared to Wuhan and Omicron strains. On the other hand, Membrane protein which was of low molecular weight appeared to be stable in all three variants. The study addresses the prominent appearance of Spike protein of Delta strain in the infected cells that might have led to increased transmissibility and cell to cell infection compared to other strains.