Maize growth, organ development, and yield formation are highly controlled by the manner in which the plant captures, partition, and remobilizes biomass and phosphorus (P). Better understanding of biomass and P accumulation, partition, and remobilization processes will improve modeling of crop resource use. However, there is still a lack of detailed data to parameterize the modeling of these processes, particularly for modern maize cultivars. A two-year (2016 and 2017) field experiment with three P fertilization treat-ments (0 (P0), 75 (P75), and 300 (P300) kg P2O5 ha 1) was conducted on a Fluvo-aquic soil (Quzhou, Hebei province, China) to collect data and quantify key processes for a representative modern maize cul-tivar (Zhengdan 958) widely grown in China. The proportions of biomass and P partitioned into various maize organs were unaffected by P application rate. Zhengdan 958 showed a much lower leaf-senescence rate than older cultivars, resulting in post-silking leaf photosynthesis being sufficient to meet grain bio-mass demand. In contrast, 50％–85％of leaf P and 15％–50％of stem P accumulated pre-silking were remo-bilized into grain, in spite of the large proportion of post-silking P uptake. Our results are consistent with the theory that plants use resources according to the priority order of re-allocation from senescence fol-lowed by assimilation and uptake, with the re-translocation of reserves last. The results also enabled us to estimate the threshold P concentrations of Zhengdan 958 for modeling crop P demand. The critical leaf P concentration for individual leaves was 0.25％–0.30％, with a corresponding specific leaf P (SLP) of 75–100 mg P m 2. The structural P concentration for leaf was 0.01％, corresponding to an SLP of 3.8 mg P m 2. The maximum P concentrations of leaves and stems were 0.33％and 0.29％. The residual P concen-tration for stems was 0.006％.