Based on the objective-weight value-assigning method, by means of establishing one comprehensive index system from four dimensions, namely natural endowment, flow input, output capacity and facilities' mechanism, this paper makes a series of experimental tests on the actual agricultural competitiveness within the 29 provincial-level areas of China from 2000 to 2016. And with application of spatial measurement model, it also makes a profound analysis upon spatio-temporal evolving rules and factors influencing China's agricultural competitiveness in hope for offering certain theoretical supports for formulating a series of targeted and differentiated agricultural competitiveness upgrading policies in the near future. The results of analysis show that: (1) China's agricultural competitiveness, featured by obvious spatial auto-correlation, is on the rise. The spatial spillover intensity presents an inverted "U-shaped" pattern. And the two sub-competitiveness indexes, namely flow input and output capacity, still keep on the upside. The overall resource endowment is relatively stable and the facilities' mechanism is witnessing a fluctuant increasing process. (2) The agricultural competitiveness in the central and western provinces continues to decline as that in the eastern provinces rises rapidly, which presents an apparent polarization. And the local-spatial clustering pattern is dominated by HH clustering mode and LL clustering mode with the characteristics of stronger stability and serious path dependency. (3) Multiple factors, including farmers' income, household-consuming level, economic basis, R&D input, planting structure and grain-variety selection, have direct effects on the spatio-temporal evolution of provincial agricultural competitiveness. At the same time, the above factors have indirect spillover effects on other provinces. (4) We should give full play of the current demonstration effect and diffusion effect brought by the agricultural competitiveness and related influencing factors to push future optimal allocation of agricultural resources, promote subsequent rational flow of the existing agricultural producing factors and plan finally-balanced development of agricultural competitiveness.