Endometrial carcinoma is the most common gynaecological malignancy. There is however a lack of curative therapies, especially for patients diagnosed with late stage, recurrent or aggressive disease, who have a poor prognosis. Interleukin (IL) 11 is a pleiotropic cytokine that has a role in a number of cancers including colon and breast cancer. IL11 was recently found to be upregulated in endometrial cancers, however the function of IL11 in endometrial cancer is not known. This study aimed to determine the effects of IL11 on endometrial cancer cell proliferation, adhesion and migration. Three endometrial cancer cell lines, Ishikawa, HEC-1A and AN3CA (derived from endometrial cancers grade I, II and III, respectively), were used to determine the effect of IL11 on endometrial cancer cell function. Cell proliferation and viability were assessed by BrdU and Wst-1 assays. Cell adhesion to the extracellular matrix proteins fibronectin, collagen I and IV, vitronectin and laminin was assessed. Modified boyden chambers were utilized to access IL11 action on migration and invasion, respectively. The specific effect of IL11 action on these processes was determined using a unique IL11 inhibitor. IL11 phosphorylated (p)-STAT3 protein abundance in all 3 cell lines but had no effect on pERK and pAKT abundance. Similarly, IL11 had no effect on cell proliferation and viability but increased adhesion of ANC3A cells to fibronectin while having no effect on the other extracellular matrix proteins. IL11 did not alter the adhesive properties of the Ishikawa and HEC-1A cells. In the AN3CA cells, IL11 treatment resulted in a 50% increase in migration and co-treatment with the specific IL11 inhibitor or a STAT3 inhibitor abolished the effect. This study shows a role for IL11 in endometrial cancer and suggests IL11 may be involved in endometrial cancer development and thus may be useful as a therapeutic target.