From inventing cutting-edge technology to designing ideal society, science fiction has always been considered as a literature of future. With the introduction of historical dimension, can science fiction provide us a new perspective to speculate on the future? In 2004, Qian Lifang’s debut novel The Will of Heaven (Tianyi), known as the representative of contemporary Chinese “historical science fiction” won both reputation and market. Her second novel Mandate of Heaven (Tianming) was published seven years later. Compared to the tremendous success of the former, it has received less attention. In existing scholarship, neither The Will of Heaven nor Mandate of Heaven has never been studied and analysed in depth whereas the concept of “historical science fiction” remains ambiguous. Taking Mandate of Heaven as an example, this paper will first discuss the generic problem of “historical science fiction” by comparing it with “alternate history.” Based on this, it continues to exam how the science fiction element is incorporated into Qian’s narrative with the aid of “time travel” and “multiverse” as narrative device. Finally, the paper will examine the conceptual experiment of “Mandate of Heaven” embodied by three characters in the book, comparing different views on the compatibility between free will and determinism. The paper concludes that “historical science fiction” is a re-invention of history. Its value lies not in defining a new genre, but in the possibility offered to readers to reflect on the dialectical relationship between fiction and history.