Increased human activities have had a significant impact on the global climate. Global warming has become an indisputable fact, but the precipitation patterns will change greatly in the future. Therefore, it has been more and more important to explore the effects of climate change on germination and seedling survival of two plants to predict the trend of the development of forest community and germplasm resources conservation as well as tend and regeneration of forest. The seed is the basis of natural regeneration of forest vegetation, and seed germination plays a key role in populations continue, population dynamics and community structure. In addition, seed germination and seedling early settle play the most sensitive role in the environmental change of the early stages of plant growth and development. Pinus koraiensis is the main constructive species in mixed conifer and broadleaved forest and has important ecological significance and economic value. Quercus mongolica is a major component tree species of the northeast natural secondary forest. We regarded the Pinus koraiensis and Quercus mongolica which were constructive species and dominant species of cool temperate zone theropencedrymion as object of this study. Space substitution method was used to simulate temperature rise and precipitation change to observe the seed germination and seedling growth under field conditions. The results showed that the germination rate of Quercus mongolica seeds decreased 13% and 18% respectively compared with provenance under elevated temperatures and precipitation increase (average annual temperature of +4.9 ℃, +330 mm) or decreased precipitation (+2.8 ℃, -249 mm) conditions, but the difference was not significant. The germination rate of Pinus koraiensis seeds increased 2.29 times compared with provenance in the case of elevated temperatures and precipitation, but decreased 64% under reduced precipitation condition, different locations have significant differences to germination rate of Pinus koraiensis seeds. It has been shown to have different effects on growth of Pinus koraiensis and Quercus mongolica seedling in different temperature and precipitation, and the plant height and basal diameter and main root length of annual Quercus mongolica seedling were significantly decreased in the case of temperature and precipitation increases and precipitation reduces, but the difference was not significant for Pinus koraiensis seedling. The interaction of temperature rise and precipitation increase or decrease make total biomass of Quercus mongolica and Pinus koraiensis seedling decrease, especially the biomass is minimum under conditions of temperature increase and precipitation increase, dropped 62% and 20% than provenance respectively. However, statistical analysis showed that biomass of Pinus koraiensis seedling had no significant differences in the three plots. Temperature rise and precipitation change decreased root to shoot ratio of the two seedlings, while no significant differences in specific leaf area. Therefore, this study showed that seed germination and seedling biomass of Quercus mongolica will decline when the temperature increased 3-5 ℃ and precipitation decreased by about 30 percent or increased two folds, however, temperature increased 3-5 ℃ and precipitation increased 1 times conducive to break dormancy and germination of Pinus koraiensis.