The LHC (CMS) discovery potential of the $e^{\pm}��^{\mp} + E^{miss}_T$ signature in the search for supersymmetry and lepton flavour violation in neutralino decays is studied. A detailed study is done for the CMS test points LM1-LM9. It is shown that for the point LM1 it is possible to detect lepton flavour violation in neutralino decays with lepton flavour violating branching $Br(\tilde��^0_2 \to ��^{\pm}e^{\mp}\tilde��^0_1) \geq 0.04 Br(\tilde��^0_2 \to e^{+}e^{-}\tilde��^0_1, ��^{+}��^{-} \tilde��^0_1)$ for an integral luminosity $10 fb^{-1}$. A discovery potential in the mSUGRA-SUSY scenario with $\tan ��= 10, ~sign(��) = +$ in the $(m_0, m_{1/2})$ plane using the $e^{\pm}��^{\mp} + E^{miss}_T$ signature is determined.

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