This research was carried out to assess the plant species diversity complex in Nasarawa State, Nigeria with a view to obtain an accurate database and inventory of the naturally occurring plant species in the State for reference and research purposes. This preliminary report covers a total of nine (9) local government areas in the state. The work involved intensive survey and several visits to the sample sites for plant identification and enumeration exercise. The diversity status of each plant and the distribution across the state were also determined using standard method. A total number of 275 plant species belonging to 61 plant families were identified out of which the families Asteraceae, Poaceae, Combretaceae, Euphorbiaceae, Moraceae and Papilionaceae were the most highly distributed across the entire study area. There was great extent of diversity in the distribution of plants across all the local governments sampled. However, the highest diversity in terms of different species was recorded in Wamba LGA. The most predominant food crop across the state was found to be Sorghum spp. This preliminary work has provided a baseline data and reference point for future taxonomical and biosystematics stratagem in Nasarawa State.