Since entering the new century，the group rising of newcomer states has become the phenomenon that receives the most outside attention in international systems. It not only direct reflects new changes in power comparisons in international structure，but also provides logic for adjustments and reform in international systems. BRICS is a multilateral platform that was formed and rapidly developed during this process，and achieved “soft balance” to the present US-led global order. “Soft power” is a feasible strategy for second-rate great powers to deal with US’ monopolar predominance. It’s not a direct challenge to the US’ military hegemony，but can use non-military methods to procrastinate，block and even sabotage superpower’s unilateral policies.International Security，Vol. 30，Nº 1，2005，p.10.">[1] This non-military method includes the strategy of mechanism arrangements，which is to have a number of countries bonding in diplomatic unity or alliance in order to restrict the power of a super nation. “BRICS，” “India-Brazil-South Africa forum” and G21 all have such characteristics，in order to help weaker countries to win more leeway when faced with powerful nations. So，they are also called “buffer” mechanisms.Orbis，Vol. 49，Nº 3，2005，pp. 401-412.">[2]In fact，from formation to specification of cooperation，BRICS coincided with Brazil’s diplomatic strategy that prioritizes “South-South Cooperation” in timeline. It not only reflects Brazil’s policy log that enhances BRICS cooperation，but also reflects its diplomatic consideration on BRICS cooperation. This report hopes to analyze Brazil’s strategic consideration from the angle of Brazil’s state identity and core goal in foreign policy，and evaluate Brazil’s participation in BRICS cooperation in the past 10 years based on this.