Serous adenocarcinoma of the endocervix is a rare carcinoma similar to the serous carcinoma of the ovary and the endometrium. We report a case of a 63-year-old woman with papillary serous adenocarcinoma arising within the endocervix, describing the clinical presentation and the morphologic characteristics of this rare neoplasm. A detailed immunohistochemical analysis on the expression of low- and high-molecular weight cytokeratins (AE1 and AE3), EMA, CEA, vimentin, B72.3, nm23, estrogen and progesterone receptors, LeuM1 (CD15), p53, Ki-67 antigen, and PCNA by tumor cells has also been carried out, which to our knowledge has not been previously reported.