In this work, we investigate the Cauchy problem of the Wadati-Konno-Ichikawa (WKI) equation with finite density initial data. Employing the ∂-generalization of Deift-Zhou nonlinear steepest descent method, we derive the long time asymptotic behavior of the solution q(x, t) in spacetime soliton region. Based on the resulting asymptotic behavior, the asymptotic approximation of the WKI equation is characterized with the soliton term confirmed by N (I)-soliton on discrete spectrum and the t − 1 2 leading order term on continuous spectrum with residual error up to O(t − 3 4 ). Our results also confirm the soliton resolution conjecture for the WKI equation. Contents 1. Introduction 2. The spectral analysis of WKI equation 2.1. The singularity at k = 0 2.2. The singularity at k = ∞ 2.3. The scattering matrix 2.4. The connection between µ ± (x, t; z) and µ 0 ± (x, t; z) 3. The Riemann-Hilbert problem for WKI equation 4. Interpolation and conjugation 5. Opening ∂-lenses and mixed ∂-RH problem 6. Decomposition of the mixed ∂-RH problem 7. Asymptotic N -soliton solution 7.1. The error function Ẽ(z) between M sol and M sol I 8. Local solvable model near phase point z = z 0 9. The small norm RHP for error function E(z) 10. Analysis on pure ∂-Problem 11.