This is a phase Ⅱ open label, non randomized study, in which sorafenib is used in combination with irinotecan, leucovorin and fluorouracil in patients with advanced colorectal cancer after failure of oxaliplatin treatment.The aim of this study is to determine the Progression-Free Survival (PFS) of Sorafenib used in combination with FOLFIRI regimen as a second front treatment in patients with advanced CRC after failure of oxaliplatin treatment, defined as the time from treatment to disease progression or death due to any cause. The other secondary endpoints are disease control rate, defined as complete response, partial response, and stable disease.Response rate,overall survival, and safety are also evaluated.