Accumulating evidence suggests that cancer cells show self-renewal ability, which plays an important role in the carcinogenesis process. However, it is not well-established into what extent self-renewal related genes are involved in this process; hence, understanding the expression and implication of these genes is critical in order to delineate the mechanisms by which cancer cells populate in their niche and subsequently lead to metastasis. Among self-renewal regulatory genes, octamer-binding transcription factor-4 (OCT4) is one of the vital factors for self-renewal and pluripotency. This master transcription factor has also been detected in tumor cells and tissues, and its expression is positively correlated with tumor grade. Here, by using in silico analysis and experimental validation, we unveil that OCT4 gene utilizes alternative promoter and alternative splicing mechanisms to generate diverse splice variants, including known and novel variants, way more complicated than previously documented. Our data reveals that some of the OCT4 variants, including OCT4B, OCT4B1, OCT4B2, OCT4B3, OCT4B5, OCT4C, and OCT4D, are expressed differentially in pluripotent and cancer cells. However, OCT4A, the most studied splice variant of OCT4, and OCT4B4, one of the novel splice variants, are exclusively expressed in pluripotent cells. Further experiments show that OCT4B4 is sharply downregulated during the course of differentiation compared to OCT4A; therefore could be considered as a better marker for studying the differentiation initiation than OCT4A. In sum, this work introduces the general and cancer-specific splice variants of OCT4, which might contribute to both pluripotency and cancer progression and to some extent, could be considered as a cancer prognostic marker, and potential therapeutic targets.