Comparisons in growth among 6-, 8-, and 11-year-old plantations of Pinus Taeda and Pinus rigida and 6-year-old Pinus rigitaeda growing in Kwang-yang district, southern part of South Korea, were made. They were so planted to facilitate the comparison by alternate row mixture. The results investigated can be concluded as follows: 1. The Pinus Taeda showed the highest growth and the lowest was Pinus rigida. The hybrid between Pinus Taeda and rigida was middle in height growth. 2. By stem analysis showed Pinus Taeda was about twice as much in the volume growth as pinus rigida. 3. Though Pinus Taeda is more sensitive to low temperature than that of Pinus rigida generally, no damage caused by coldness was observed in plantation of Pinus Taeda in Kwang-yang area. 4. Some protections against wind damage in young Pinus Taeda plantation are needed.