Candida albicans is a diploid, opportunistic fungal pathogen, and commonly colonizes on healthy humans. Usually, the host immune system keeps this pathogen under control. However, C. albicans can outgrow and cause serious infection particularly in the immunocompromised individuals. It usually forms biofilm, which is a complex structure of aggregation of microorganisms and has a significant consequence for drug resistance and for human health. Preventing the biofilm formation becomes an important health concern. There is no sufficient information about protein-protein interaction and others about C. albicans. On the contrary, Saccharomyces cerevisiae, cousin of C. albicans, is well studied in all aspects and lots of microarray data are available as well as sufficient ChIP-chip data. Some studies have tried to construct the network for its cell cycle and other functions. Hence, we try to use the gene expression data of C. albicans combined with the protein-protein interaction of S. cerevisiae reasonably to find the important information that affects the formation of biofilm. From some review papers [1-3], we have already known the transcription factors such as Cph1 and Efg1 will affect the formation of biofilm and we would like to find other important genes about biofilm with the two genes as a starting point. We construct the regulatory network of C. albicans and find the potentially important transcription factors and functional group that is potentially related to biofilm formation. This study provides a good way to investigate the regulatory network in a less-studied organism.