Objective: To investigate the value of quantitative parameter of tissues-4D dynamic contrast enhanced MRI(T4D-DCE-MRI) in diagnosis of primary liver cancer(PLC) and the correlation between perfusion parameters and pathological results, including the pathological grade, microvascular density (MVD) and vascular endothelial growth factor (VEGF) by contrastive analyzing the results of pathology and the results of T4D-DCE-MRI. Methods: 63 patients with liver lumps verified by pathological findings were examined by DCE-MRI and the images were analysised by Tofts model ,two-compartment model of T4D software on the workstation of Siemens. The perfusion parameters including the transfer constant(Ktrans), the volume of extravascular extracellular space per unit volume of tissue(Ve) and the rate constant(Kep) were calculated on lesion and normal liver tissues which as reference parameters.The relative parameters were the ratio of lesion parameters / reference parameters . The parameters of precancerous lesions and parameters of the PLC were tested for differences. The parameters were contrastive analyzed respectively with pathological grade, MVD and VEGF. Statistic analyses were completed by using SPSS 16.0. Results: 1.pathological results:There were 12 cases of precancerous lesions and 51 cases of PLC in the 63 patients. Among 51 cases of PLC, 10 ones were high differentiated, 34 ones were middle differentiated and 7 ones were low differentiated. 22 ones VEGF expressed negative(-), 25 ones VEGF expressed low level positive(+),4 ones VEGF expressed middle level(++) and no one expressed high level(+++).The patients MVD marked by CD34 were in the range of 10 and 100. 2.The differences between parameters of precancerous lesions and parameters of the PLC: 2.1 In the two groups, the difference of lesion Ktrans and relative Ktrans had statistical significance,t=3.851,3.837, P=0.000,0.000 respectively.When lesion Ktrans was 0.294(min-1),the sensitivity of the diagnosis of PLC was 0.922 and the specificity was 0.750. When relative Ktrans was 2.064,the sensitivity of the diagnosis of PLC was 0.745 and the specificity was 1.000. 2.2 In the two groups, the difference of lesion Ve and relative Ve had statistical significance,t=3.755,5.613,P=0.001,0.000 respectively. When lesion Ve was 0.427,the sensitivity of the diagnosis of PLC was 0.471 and the specificity was 1.000. When relative Ve was 4.277,the sensitivity of the diagnosis of PLC was 0.882 and the specificity was 0.917. 2.3.In the two groups, the difference of lesion Kep and relative Kep had no statistical significance,t=1.419,-1.377,P= 0.161,0.174 respectively. 3.The correlation between perfusion parameters and the pathological grade: The lesion Ktrans,lesion Kep,lesion Ve and relative Ktrans,relative Kep,relative Ve had no correlation with the pathological grade, r = 0.158, 0.080, 0.117,0.126,0.221,-0.133, P= 0.269,0.576,0.414,0.380,0.119,0.351 respectively. The values of lesion Ktrans,lesion Kep,relative Ktrans and relative Kep of middle differentiated PLC were biggest. 4. The correlation between perfusion parameters and MVD: The lesion Ktrans had a positive correlation with MVD,r=0.533,P=0.000. The lesion Kep,lesion Ve had no correlation with MVD, r=0.219,0.150,P=0.123,0.295 respectively. The relative Ktrans,relative Kep had a positive correlation with MVD,r=0.791, 0.717,P=0.000,0.000 respectively.The relative Ve had no correlation with MVD, r=-0.155,P=0.278. 5. The correlation between perfusion parameters and VEGF The lesion Ktrans,lesion Kep and lesion Ve had no correlation with VEGF.r =0.023,0.016,0.066,P=0.874,0.911,0.644 respectively.The relative Ktrans,relative Kep had a positive correlation with VEGF,r= 0.398, 0.379, P=0.004,0.006 respectively. Conclusions: The quantitative analyzing of T4D-DCE-MRI could reflect the microcirculation function of PLC. The perfusion parameters of T4D-DCE-MRI have great reference value not only in identifying the precancerous lesion and PLC but also in evaluating pathological characteristics.