The paper is organized as follows. In the next section, we present the particle content together with the flavor symmetry of our model. In Sec. III, we show the neutrino masses are generated in 1-loop level and how the parameters are constrained by the low energy neutrino oscillation data. Sec. IV analyzes leptogenesis included flavor effects in each heavy right-handed neutrino spectrum. Then we give the conclusion in Sec. V, and in Appendix we briefly discuss the vacuum alignment challenge. Unless flavor symmetries are assumed, particle masses and mixings are generally unde- termined in gauge theory. To understand the present neutrino oscillation data we consider A$_{4}$ flavor symmetry for leptons, and simultaneously the existence of LHC signal and the baryon asymmetry of the Universe to be explained at TeV scale we also introduce an extra discrete symmetry Z$_{2}$ in a radiative seesaw [19]. Especially, we introduce a 5-dimensional operator in the lagrangian which is invariant under A$_{4}$ × Z$_{2}$ × Z$_{4}$ to have non-zero low energy CP violation in neutrino oscillation and non-zero high energy cosmological CP vio- lation which is responsible for BAU. Here we recall that A$_{4}$ is the symmetry group of the tetrahedron and the finite groups of the even permutation of four objects. Its irreducible representations contain one triplet 3 and three singlets 1 , 1 ′ , 1 ′′ with the multiplication rules are 3 ⊗ 3 = 3$_{s}$ ⊕ 3$_{a}$ ⊕ 1 ⊕ 1 ′ ⊕ 1 ′′ , and 1 ′ ⊗ 1 ′ = 1 ′′ . Let’s denote two A$_{4}$ triplets, ( a$_{1}$, a$_{2}$, a$_{3}$ ) and ( b$_{1}$, b$_{2}$, b$_{3}$ ), then we have where ω = e i 2 π/ 3 is a complex cubic-root of unity. The field content under SU (2) × U (1) × A$_{4}$ × Z$_{2}$ × Z$_{4}$ of the model is assigned as Table-II Hence its Yukawa interactions in the lepton sector, which is invariant under SU (2) × U (1) × 4 3$_{s}$ ∼ ( a$_{2}$b$_{3}$ + a$_{3}$b$_{2}$, a$_{3}$b$_{1}$ + a$_{1}$b$_{3}$, a$_{1}$b$_{2}$ + a$_{2}$b$_{1}$ ) , 3$_{a}$ ∼ ( a$_{2}$b$_{3}$ − a$_{3}$b$_{2}$, a$_{3}$b$_{1}$ − a$_{1}$b$_{3}$, a$_{1}$b$_{2}$ − a$_{2}$b$_{1}$ ) , 1 ∼ a$_{1}$b$_{1}$ + a$_{2}$b$_{2}$ + a$_{3}$b$_{3}$ , 1 ′ ∼ a$_{1}$b$_{1}$ + ωa$_{2}$b$_{2}$ + ω $^{2}$a$_{3}$ b$_{3}$ , 1 ′′ ∼ a$_{1}$b$_{1}$ + ω $^{2}$a$_{2}$ b$_{2}$ + ωa$_{3}$b$_{3}$ , (2) II. FLAVOR A$_{4}$ SYMMETRY AND A DISCRETE SYMMETRY Z$_{2}$ × Z$_{4}$