The calcination temperature effects on the adsorption characteristics of Badau Belitung kaolin has been studied. The adsorption characteristics examined were specific surface area (SSA), physisorption isotherms, pore size diameter, and pore size distribution. The study was conducted by treating kaolin with 1M NH4Cl and NH4NO3 on hot plate magnetic stirrer for 24 hours. The treated samples then washed until 6.5 pH and dried. The dry samples were calcined at 400, 500, 600 and 700 °C for 3 hours. The samples were characterized using BET methods in Quantachrome NovaWin 11.0 version at 77.3 K and DTG-TGA. The results showed that the treatment by 1 M NH4NO3 could improve the SSA of kaolin compared to the use of NH4Cl with the same level of molarity and the temperature of metakaolin formation is at 509 °C. The results also suggested that the calcination above the temperature of metakaolin formation could lead to increase level of SSA.