The objective of the study was to investigate the effects of dietary blend organic acids and sodium bicarbonate supplementation on the physiology and growth performance of pigs. In trial 1, thirty LYD cross breed finishing castrate boar were randomly allocated into 3 arrangements (control, 0.4% organic acid and 1% sodium bicarbonate) according to respective body weight with 2 replications each treatment and 5 pigs per replication. ad libitum feeding and drinking water, the duration of the trial was 6 weeks. For data collection, daily feed intake, body weight, rectal pH value and blood pH value were measured weekly. All the pigs were slaughtered in the end of the trial for measuring carcass, gastrointestinal and blood pH value. In trial 2, 15 and 20 LYD cross breed sows and gilts, respectively, were randomly allocated into 3 arrangements (control, 0.4% organic acid and 1% sodium bicarbonate) according to respective body weight with 15 (sow and gilt were 5 and 10 respectively) replications each treatment and 1 pigs per replication. Before mating, ad libitum feeding and drinking water; after mating, restrict feeding and ad libitum water, the duration of the trial was 24 weeks. For data collection, daily feed intake, rectal temperature, vagina pH value, body weight and back fat were measured weekly, and in addition, rectal temperature and vagina pH value were measured per two hours while heat duration, and blood, fecal and urine pH value were measured in the prophase, medium phase and the late stage. After farrowing, record daily feed intake, body weight, blood and milk pH value, milk composition, immunoglobulin content; and record weight gains and diarrhea times of piglet. In trial 3, 20 LYD cross breed growing pigs, were randomly allocated into 4 arrangements (control, 1%, 2%, and 3% Citric acid) according to respective body weight with 5 replications each treatment and 1 pigs per replication. Restrict feeding and ad libitum water drinking, the duration of the trial was 4 weeks (include 3 weeks adaptation phase and 1 week total excreta collect phase), and for data collection, daily feed intake and excreta pH value, measure vagina and rectal pH value twice per week; in excreta collect phase, collect at 00:00, 06:00, 12:00 and 18:00 and weigh, calculate the digestive and metabolic rate of feed intake in collect phase. The results of trial 1 shows that, the sodium bicarbonate group tended to have better weight gain (P＞0.05) than the other two groups. About the rectal pH value, the organic acid group has significantly decrease (P＜0.05) in the first week. About the gastrointestinal tract pH value, the organic acid group is higher than the other two groups, and has significantly difference (P＜0.05) in the duodenum and the front jejunum; the pH value before and after removing urine, the sodium bicarbonate group is significantly the highest and the organic acid group is the lowest (P＜0.05). The results of trial 2 shows that, in first heat phase, about the rectal temperature and the vaginal pH value, the sodium bicarbonate group is significantly the highest and the organic acid group is the lowest (P＜0.05). About the urine pH value, the sodium bicarbonate group is significantly the highest (P＜0.001). After farrowing, about the weightlessness of sows and the placenta pH value, the organic acid group has lower trend (P＞0.05). About the mineral content in milk, content of copper and zinc is significantly the highest (P＜0.05); In amino acids concentrations, aspartate, glutamate, serine, glycine, threonine, phenylalanine, leucine, and lysine are significantly higher (P＜0.05), and the sodium bicarbonate group has higher trend（P＞0.05）; about the fatty acids content, the organic acid and the sodium bicarbonate groups have higher trend (P＞0.05). The piglets which were born by the sows of the organic acid group have significantly decreasing of diarrhea. The results of trial 3 shows that, when citric acid supplementation to 3% the feces pH significant highest, and significant lowest when supplementation 1% citric acid; supplementation 1% citric acid the urine pH significant highest, lowest on 2% supplementation. In vagina and rectal pH, have lower trend but no significant when citric acid supplementation. In conclusion, organic acids supplementation can reduce rectal, vagina, bladder and urine pH value. Maybe can reduce the chance of infection, the diarrhea times of piglet also reduce; but when sodium bicarbonate supplementation can reduce the effects of high temperature on pigs, the vagina, bladder and urine pH value were increase; when citric acid supplementation can increase part of mineral absorb and utilization.