Background This study aimed to investigate multi-slice CT contrast-enhanced presentation of gastric cancer and its correlation with histo-differentiation and p53 and P-glycoprotein (P-gp) expression. Methods Sixty-six patients with gastric cancer in the present study underwent a multi-slice CT preoperative routine and dual-phase contrast-enhanced examination of the upper abdomen; postoperative specimens were used to determine histo-differentiation and the expression of p53 and P-gp. The correlation of multi-slica CT contrast-enhanced presentation with histo-differentiation and expression of p53 and P-gp was analyzed. Results The dual-phase contrast-enhanced ratio (CER) was not correlated with the histo-differentiation of gastric cancer (P＞0.05). Positive expression of p53 and P-gp was significantly higher in the cases of layered or heterogeneous enhancement than in the cases of homogenous enhancement (P＜0.05). Positive expression of p53 was also correlated with the arterial phase CER, tumor size and lymph node metastasis (P＜0.05), but not with infiltration thickness of the gastric wall, nor was it correlated with the portal phase CER (P＞0.05). Positive expression of P-gp was only correlated with the portal phase CER (P=0.005). Conclusions Differently enhanced pattern and CER of the arterial and portal phase in gastric cancer correlate with its different histo-differentiation and expression of p53 and P-gp respectively. In addition, tumor size and lymph node metastasis of gastric cancer relate to the expression of p53.