The AILDE (Auto In Silico Ligand Directing Evolution) Server is developed according to the CSO (Computational Substitution Optimization) protocol, which was designed to automatically perform computational substitution, energy minimization, and binding affinity evaluation. AILDE is a new computational server to automatically perform substitution-scanning mutagenesis of ligand and could be used as a general strategy of Hit to lead (H2L) optimization in drug and agrochemical design.