Top quark pair cross section measurements in CMS

This document presents the latest results in the measurement of the top-quark pair production cross section obtained with data collected by the CMS detector at LHC accelerator. The analyses are performed in the dilepton, single lepton and full hadronic decay modes. Additionally to the inclusive measurements of $\mathrm{\sigma_{\mathrm{t\bar{t}}}}$ at 7, 8 and 13$\mathrm{\;TeV}$, the CMS collaboration provides for the first time the cross section at 5.02$\mathrm{\;TeV}$. Results are confronted with the latest and most precise theoretical calculations.