Wilms’tumor gene (WT1) 17AA(-)/KTS(-) isoform alters morphological changes, motility and invasion of cancer cells that may involve in cell attachment to extracellular matrix (ECM) and its receptor integrin subunits. The objective of this study is to determine effect of WT1 17AA(-)/KTS(-) cell adhesion on each type of ECM coating substratum in ovarian cancer and fibrosarcoma cell line. Constitutively expression of WT1 17AA(-)/KTS(-) in both cell lines were determined cell adhesion assay to Fibronectin, Collagen I or Laminin substratum compared to mock control cells. We found that WT1 17AA(-)/KTS(-) reduced the ability of cancer cells to Fibronectin substratum. This data suggested that 17AA(-)/KTS(-) may has function in cancer cells adhesion mechanism and may has highly possible to involve the function of Fibronectin substratum binding-integrin subunits that related to cancer cells morphological changes, motility and invasion. Bull Chiang Mai Assoc Med Sci 2009; 42: 233-241.