Objective To investigate C‐reactive protein in patients with acute brain injury (CRP) ,platelet (PLT) dynamic chan‐ges and clinical significance .Methods A hospital in 2014-2015 120 cases of acute brain injury ,depending on whether surgery di‐vided into :64 cases of surgical group ,56 cases of non‐surgical group .According to Glasgow Outcome Scale (Glasgow Outcome Score ,GOS) divided into 61 cases of poor prognosis group (GOS 1 -3 scores) ,59 patients with good prognosis (GOS 4 -5 scores) .Another choice the same period 50 cases of healthy control group .After the patients were injured 1 d ,3 d ,7 d dynamic tes‐ting CRP ,PLT levels .Results The surgical group and the non‐surgical group patients after injury 1 d serum CRP levels were sig‐nificantly increased ,decreased gradually after all ,the two groups showed a downward trend ,but the surgery group were decreased slowly ,always maintain a high level ,still significantly at 14 d the control group (P<0 .05) .Patients with non‐surgical group de‐creased significantly ,significantly higher than the decline in the extent of the surgery group (P<0 .05) .Surgical and non‐surgical group patients after injury when PLT 1 d showed no increased after 3d began to rise ,increased significantly when 7 d ,PLT levels were elevated degree of surgical group was significantly higher than the non‐surgical group (P<0 .05) .Good prognosis group and a poor prognosis group ,serum CRP on admission were increased ,and reached a peak after 1 d ,after declining in both groups ,with good prognosis group decreased significantly ,while the poor prognosis group ,no significant decline in CRP levels ,continued high levels of state for a long time When postoperative 7d still significantly higher than the normal level (P<0 .05) .At each time point the poor prognosis group ,serum CRP levels were significantly higher than the good prognosis group (P< 0 .05) .When the good prognosis group and a poor prognosis group was mean change 1d PLT little water ,began to increase after the 3 d were poor progno‐sis group of patients was significantly higher than 7 d PLT good prognosis group (P<0 .05) .Conclusion Patients with acute brain injury CRP ,PLT dynamic changes are certain rules ,is to determine the acute phase of the disease of brain injury and prognosis of change .