Germination is a key process in the life cycle of plants and is one of the stages most sensitive to salinity, which involves numerous mechanisms and multistage processes. A comprehensive understanding of the germination process and salt-tolerance mechanisms help to assess the salt tolerance of wheat genotypes at the early growth stage. In this study, 200 mM NaCl was used for treatment, under which the germination performance of different varieties showed significant differences (p < 0.01) in the pre-test treated with different concentrations (0, 50, 100, 150, 200, and 250 mM NaCl), 12 wheat genotypes with significant differences in salt tolerance (obtained from a germination experiment of 30 varieties) were cultured in NaCl solution containing (0 and 200 mM NaCl) to investigate the crucial parameters controlling seed germination and clarify the salinity tolerance mechanisms in wheat. The results indicated that salinity significantly affected the utilization of water and storage materials in seeds due to the disrupted K+/Na+ homeostasis and inhibited α-amylase activity. Furthermore, a significantly negative correlation was observed between Na+ content and α-amylase activity, while the seed germination suffered most from the elevated Na+ content (either osmotic stress or ion toxicity), which was found to be negatively correlated with salt tolerance. We concluded that higher water uptake rate and α-amylase activity are related to the salt tolerance of wheat. Na+ could affect seed germination by inhibiting α-amylase activity. Meanwhile, a lower K+ efflux was found in the salt-tolerant accession compared with the salt-sensitive variety, indicating that the K+ retention mechanism affects the salt tolerance of wheat. Taken together, the germination ability parameters such as amylase activity and K+ efflux can be used as convenient high-throughput tools allowing rapid screening of hundreds of lines at the early growth stage.