A cost-free modification of second-order electron propagator theory (ex-SCS-EP2) to improve the description of ionization energies based on spin-component-scaled approximation is proposed. The relaxation part (PRX) and correlation part (PRM) in second-order self-energy are partitioned into parallel-and anti-parallel-spin component then scaled separately. The scaling factors are optimized with 23 valence orbital energies and results shown that ex-SCS-EP2 performs significantly better than regular EP2, SCS-EP2 and OVGF with 0.22 eV of mean absolute error (MAE) and 0.11 eV of mean absolute deviation (MAD). The effects of SCS parameters on self-energy are also examined to ensure better description in total correlation energy. (C) 2017 Elsevier B.V. All rights reserved.