📕 Similarity searching is a process to find compounds that are similar to a target compound, which is useful in discovering potential drugs.this study is to optimize weights of different similarity measures in data fusion for searching chemical database by applying genetic algorithm (GA).Comparisons of different coefficient fusions were carried out.Using combination with weights ranging between 0.0 and 1.0 generated by genetic algorithm, gave a better number of active than the non-weighted combination.