The California poppy ($Eschscholzia$ $californica$) has been known as a hardy annual and its seeds are usually sown outdoor in mild climates or in early spring in colder areas to be planted for landscape, green tourism, urban park, and highway beautification along roadsides. In this study, to improve the final germination percentage (FGP) and to fasten germination speed in the California poppy seeds, we investigated to find proper seed-priming conditions such as chemicals, priming-temperature, and seed dry content (DC, %) for long-term storage after priming. As for seed materials, the California poppy seeds were sorted by seed-diameter. The biggest group with 1.4-2.0 mm in seed-diameter showed higher FGP at $25^{circ}C$ compared with the other smaller groups. Moisture contents (MC, %) of non-primed seeds was 7.1% but MC of 100 mM $KNO_3$-primed seeds and DW-primed seeds was 37.8% and 37.5%, respectively. The following study was conducted to find proper drying content (DC, %) within primed seeds for maintaining seed viability after long-term storage. 100 mM $KNO_3$-primed seeds with 70% DC showed the best FGP and $T_{50}$ results compared with the other treatments including non-primed seeds. Especially, DW-primed seeds with high DC showed very low FGP and delayed $T_{50}$ because the seeds decayed and lost germination ability during seed storage. In conclusion, it was recommended to keep high seed viability and successful priming effect during long-term storage, the California poppy seeds were primed at $10^{circ}C$ with 100 mM $KNO_3$ for 24 h and stored at 70% DC within the primed seeds.