To enrich the basic information of KRAB-A gene by analyzing the molecular characteristics of KRAB-A and performing phylogenetic analysis of KRAB proteins in N. ceranae and other species, the amino acids sequence of KRAB-A was predicted using ORF tool in NCBI database. Related software in ExPASy website were employed to predict and analyze the hydrophilicity, signal peptide, phosphorylation site, secondary structure and tertiary structure of KRAB-A.Phylogenetic tree based on KRAB-A protein was constructed by Mega 11.0 software using Neighbor-joining method. The results demonstrated that KRAB-A gene can encode 1018 amino acids; the molecular formula of KRAB-A protein was C₅₃₁₄H₈₅₂₆N₁₅₂₂O₁₅₅₆S₄₃, the molecular weight was 120.00 kDa, the hydrophilic point was 9.33, the lipid solubility coefficient was 79.20, and the hydrophilicity was -0.75; KRAB-A contained 41 serine phosphorylation sites, 21 tyrosine phosphorylation sites, 16 threonine phosphorylation sites, one H2C2 motif, and no