[en] Based on the picture of nonlinear and non-parabolic symmetry response, i.e., Δn₂(I) ∼ ρ(a₀+a₁x-a₂x²), we propose a model for the transversal beam intensity distribution of the nonlocal spatial soliton. In this model, as a convolution response with non-parabolic symmetry, Δn₂(I) ∼ ρ(b₀+b₁f-b₂f² with b²/b¹ > 0 is assumed. Furthermore, instead of the wave function ψ, the high-order nonlinear equation for the beam intensity distribution f has been derived and the bell-shaped soliton solution with the envelope form has been obtained. The results demonstrate that, since the existence of the terms of non-parabolic response, the nonlocal spatial soliton has the bistable state solution. If the frequency shift of wave number β satisfies 0 < 4(β - ρb₀/μ) < 3η₀/8α, the bistable state soliton solution is stable against perturbation. It should be emphasized that the soliton solution arising from a parabolic-symmetry response kernel is trivial. The sufficient condition for the existence of bistable state soliton solution b₂/b₁ > 0 has been demonstrated