Molecular dynamics (MD) based study of nanocrystalline (NC) Al and CNT (carbon nanotube) reinforced NC Al specimens having grain sizes ~9 nm have been carried out under tensile loading using hybrid potentials for different temperatures (10 K, 300 K and 681 K) at a particular strain rate of 1010 s-1. Structural variation and defect evolution during the deformation have been investigated. An enhancement in both strength and ductility is observed in case of the CNT embedded NC Al specimens with respect to NC Al specimen and such improvement is significant in case of (30,30) CNT embedded NC Al specimen. It is also found that NC Al matrix is fractured first, then the CNT at lower test temperature, whereas at high temperature, the CNT fractures before the matrix.