<p>The task of cell type annotation is essential in the overall analysis workflow of spatial transcriptomics data. Although a variety of methods have been proposed for cell type annotation in spatial transcriptomics, each has certain limitations. Therefore, it is necessary to systematically summarize and review these methods, so that researchers can apply them according to their specific needs or gain insights to guide the development of future spatial transcriptomics cell type annotation approaches. This review takes cell type annotation methods developed for different spatial transcriptomics technologies as the entry point and provides a detailed overview of each method applicable to the two types of technologies from three perspectives: the time of proposal, the implementation approach, and the strengths and limitations. Furthermore, it introduces an innovative classification of these methods based on whether they require single-cell transcriptomic reference data, offering a more refined and comprehensive summary of spatial transcriptomics cell type annotation methods for researchers in the field. This review serves as a resource for researchers applying or developing cell type annotation methods in spatial transcriptomics.</p>