Future climate change tends to be with features of CO_2 concentration and temperature increasing, which will produce significant influence on agriculture. This paper mainly focused on the effect of CO_2 concentration and temperature increasing on rice seedling physiological characteristics of rice in southern China by simulating 3 climate scenarios, i.e., CO_2 concentration 400mmol·mol~(-1) and increasing 0℃ as control treatment (CK), 550mmol·mol~(-1) and increasing 2℃ compared with CK as middle treatment (M), 700mmol·mol~(-1) and increasing 4℃ compared with CK as high treatment (H). The seeds were placed into different treatments about 10 days after soaking and accelerating germination, then monitored relevant indexes of seed germination and physiological characteristics. The results showed that (1) as CO_2 concentration and temperature increasing simultaneously, the height of seedling, the length of root, the number of root longer than 1cm, and dry weight of root and seedling and vigor index increased. Compared with CK, under H, height of rice seedling was higher 5.78cm, root length was 12.91% longer, dry weight of root and seedling was 2.6 times than CK, vigor index was 3.1 times than CK; germination vigor, germination rate and germination index achieved highest in medium treatment; (2)Along with CO_2 concentration and temperature increasing simultaneously, malonicdial dehyde (MDA) content and soluble sugars (SS) content were gradually decreasing, proline (Pro) content was highest in medium treatment, soluble protein (SP) content and catalase (CAT) activity were increasing. In general, the future climatic change characteristics of CO_2 concentration and temperature increasing simultaneously had no obvious adverse effect on rice germination and seedling growth with CO_2 concentration increasing to 550mmol·mol~(-1) and 700mmol·mol~(-1), temperature increasing 2-4℃. But the nutrient elements would be limited in germination and seedling period.