Objective: To investigate the floristic diversity in three remaining urban forest fragments in Palmas, Tocantins, aiming to understand the structure and floristic composition and their importance for urban biodiversity conservation. Theoretical Framework: Based on concepts of phytosociology and biodiversity conservation, highlighting the importance of urban fragments for the preservation of native flora and the challenges posed by increasing urbanization. Method: Setup of 10 plots, each measuring 20x50 meters in the three studied fragments. All individuals with a circumference at breast height (CBH) equal to or greater than 10 cm were sampled. The phytosociological data were collected and analyzed using FITOPAC software. Results and Discussion: A total of 1,346 individuals belonging to 67 species and 44 families were found. The observed phytophysiognomies were cerrado sensu stricto and cerradão. The species Connarus suberosus, Caryocar brasiliense, and Qualea parviflora showed higher occurrence and wider distribution. These results reflect the richness and diversity that can be found in remaining fragments of the Cerrado. Research Implications: The practical and theoretical implications of this research are discussed, providing results that influence conservation practices and sustainable management in urban areas. Originality: Universidade Federal do Tocantins, Palmas, Tocantins, Brasil. Value: This study contributes to the literature by providing a detailed analysis of the floristic composition of urban fragments of the Cerrado, highlighting their importance for biodiversity conservation in urban areas. The relevance of this research is evidenced by the proposed strategies for the preservation of native species in Palmas' urbanization plan.