One of the most important objectives of the Agreement on Sanitary and Phytosanitary Measures(SPS Agreement) is that sanitary and phytosanitary measures necessary to protect human, animal or plant life or health to minimize their negative effects on trade. One hands, WTO Members have the fundamental right to take SPS measures necessary for the protection of their people, animals and plants from health risks. The other hands, they have the basic obligation to ensure that the measures are based on scientific principles and not maintained without sufficient scientific evidence. But In exceptional circumstances, The members have the right to take the provisional SPS measures under article 5.7 of the SPS Agreement. Article 5.7 of the SPS Agreement sets out four requirements which must be met in order to adopt and maintain a provisional SPS measure. These requirements are: (1) the measure is imposed in respect of a situation where “relevant scientific evidence is insufficient”; (2) the measure is adopted “on the basis of available pertinent information”; (3) the Member which adopted the measure “seek[s] to obtain the additional information necessary for a more objective assessment of risk”; and (4) the Member which adopted the measure “review[s] within a reasonable period of time. This thesis focus on the interpretation of the requirements of the Article 5.7, and aims at highlighting a number of lessons to be learnt from the present WTO system concerning provisional SPS measures.