Formation of bio?lm on solid surfaces is a common feature of microalgae, which is tightly associated with the properties of microalgae and substratum material. Increasing interests on microalgae biofilm attached cultivation or antifouling require to determine the effect of material surface physico-chemical characteristics on algal adhesion. However, reference researches are usually inconclusive and do not work well. This work is to evaluate the influence of hydrophobicity/hydrophilicity of substratum on microalgae adhesion. First, this work reported a novel method for surface hydrophobic modification of bisphenol-A Epoxy (EP) resin by adding hydrophilic diethanolamine (DEA) or hydrophobic polymethylhydrosiloxane (PMHS). The results showed that the water contact angles of the modified EP resin coatings were regulated in the range from 36.80? to 98.34?. With the increase of DEA, the water contact angle linearly declined. While, with the increase of PMHS, the water contact angle linearly increased. However, little difference between the two kinds of modified EP materials was observed through the characteristics of morphology, surface texture and roughness. Then, the static adhesion of microalgae C. vulgaris and S. dimorphus was investigated. The results showed that both C. vulgaris and S. dimorphus could adhere on all the coating surfaces with different wettabilities, but preferred to adhere more and faster on the hydrophilic ones. The linear relationships of two microalgae between their maximum adhering capacities and the water contact angles of the modified EP coatings were existed respectively. Hydrophobic surface had less adhered algal cells. The adhesion amount of S. dimorphus was larger than that of C. vulgaris.