While the extant Tibetan biographies of Atiśa Dīpaṃkaraśrījñāna (982–1054) are abundant, most of the datable ones were completed three hundred years after Atiśa’s death. However, two Tangut manuscripts offer early biographical accounts of Atiśa as they were written in the Tangut State (1038–1227). Centering around Atiśa’s life at Vikramaśīla and his journey to Tibet, the narratives within the Tangut texts both resonate with and diverge from the more conventional accounts found in sources like the Extensive Biography (Rnam thar rgyas pa) and the Well-Known Biography (Rnam thar yongs grags). As a result, these Tangut sources emerge as invaluable resources for studying the biographical tradition of Atiśa, as well as the dissemination of his life story in the unique context of the Tangut State during the rise of Tibetan Buddhism therein. This paper introduces and translates two Tangut biographical accounts along with relevant Tibetan textual materials. Its aim is not only to present these new sources but also to utilize them to examine the development of Atiśa’s biographical tradition. Furthermore, it demonstrates how Tibetan and Tangut studies can be methodologically integrated.