The rice (Oryza sativa) gene Os01g61900 encodes a protein containing a CCT domain. Members of this gene family are predominantly involved in regulating flowering time and thus influence heading date and final yield formation in rice. Bioinformatic analysis, subcellular localization, tissue-specific expression profiling, and prokaryotic expression vector construction were conducted for Os01g61900 , followed by prokaryotic induction and purification of its recombinant protein. Key findings include: 1) Os01g61900 encodes a nuclear-localized CCT transcription factor with two distinct α-helical structures in its core domain. Homologs of this gene were identified in grape (Vitis vinifera, two homologs), Arabidopsis thaliana, maize (Zea mays), sorghum (Sorghum bicolor), Brachypodium distachyon, and Populus trichocarpa. Phylogenetic analysis revealed that Os01g61900 clusters with homologs from maize, B. distachyon, and sorghum. 2) Os01g61900 exhibited higher expression levels in roots and panicles of rice. 3) Subcellular localization assays via protoplast transformation and tobacco (Nicotiana tabacum) cell transfection confirmed nuclear localization of the encoded protein. 4) A prokaryotic expression system was successfully established, enabling the production and purification of recombinant Os01g61900 protein in vitro. These results lay a foundation for further functional characterization of Os01g61900 and its molecular mechanism in regulating rice heading date.