Phosphorylation of proteins plays an important regulatory role at almost all levels of cellular organization. Molecular dynamics (MD) simulation is a promising tool to reveal the mechanism of how phosphorylation regulates many key biological processes at the atomistic level. MD simulation accuracy depends on force field precision, while the current force fields for phospho-amino-acids have resulted in notable inconsistency with experimental data. Here, a new force field parameter (named FB18CMAP) is generated by fitting against quantum mechanics (QM) energy in aqueous solution with φ/ψ dihedrals potential energy surfaces optimized using CMAP parameters. MD simulation of phosphorylated-dipeptides, intrinsically disordered proteins (IDPs), and ordered (folded) proteins show that FB18CMAP can mimic NMR observables and structural characteristics of phosphorylated-dipeptides and proteins more accurately than the FB18 force field. Then we constructed virtual screening platform based FB18CMAP force field. To test the performance of the platform, the phosphorylated glycogen synthase kinase 3 associated with alzheimer’s disease was used to screen the suitable inhibitor. The results indicate that FB18CMAP could success in hitting the potential inhibitor among Top 10 score. The validation of biochemistry experiment was in progress.