This study aimed to delineate the seed transfer zone of Pinus densiflora. After generating transfer functions based on growth characteristic data from 10 pine test sites for 36 seed sources and six bioclimatic variables, the critical seed transfer distance for each climate variable was calculated. Based on our results, seed transfer zones were delineated by overlaying maps for all climate variables. In the pine provenance test, seeds from eastern Korea generally showed superior growth at each test site. Temperature-related variables accounted for a higher proportion of the selected bioclimatic variables than precipitation-related variables. Additionally, warm-to-cold seed transfer in eastern Korea and cold-to-warm seed transfer in central and southern Korea were overestimated, widening the seed-transfer zone. Examining the long-term growth of the trees, introducing additional variables, and applying a model with a higher level of rationality to the transfer function are necessary for delineating the optimal seed-transfer zone.