ECFA was signed in Chongqing on June 29, 2010. Cross-Strait economic trade development will be expected to reach a new milestone after it went into effect on September 12, 2010. Early harvest list of tariff concession on ECFA covers 539 Taiwanese products to Mainland and 267 mainland Chinese products to Taiwan. The tariff will be zero out in three time slots within two years. This research is focus on pros and cons for Taiwan after signing ECFA, besides, propose fourteen assessment indicators as measure the benefits of ECFA, meantime, process the SWOT analysis after signing the ECFA. The last, deeply exploring the relationship between Cross-Strait economic development, and it will propose as the reference for the Cross-Strait policy.