To screen cold-tolerant germplasm resources of japonica rice at the germination stage in Heilongjiang Province, this study used 344 japonica rice varieties as materials and applied two treatments: 25 ℃ (normal temperature) and 15 ℃ (low temperature). Indicators such as germination energy, germination rate, germination index, and mean germination time were measured. Relative values were calculated, and comprehensive evaluation of cold tolerance at the germination stage was conducted using principal component analysis, cluster analysis, and a comprehensive evaluation value (D-value). The results showed that low-temperature stress significantly reduced germination energy (mean decrease of 86.12%), germination rate (mean decrease of 7.62%), and germination index (mean decrease of 52.54%), while significantly prolonging the mean germination time (2.48 days at normal temperature vs. 5.38 days at low temperature). Significant differences in cold tolerance were observed among varieties. Principal component analysis transformed four relative indicators into two comprehensive indices, with a cumulative contribution rate of 88.172%. Cluster analysis divided the tested materials into four cold-tolerance grades; the first group (cold-tolerant type) included 107 accessions, with D-values ranging from 0.895 to 0.751. Finally, ten highly cold-tolerant germplasms, including Dongnong 415, Beidao 16, and Puyu 831, were selected.