Gastric cancer as a dreaded disease which occurs in the digestive system of human being remain a threat to the medical world. Bioactivity of series of designed and synthesized molecular compounds containing triazole and pyrimidine moieties were subjected to quantum chemical calculations using B3LYP/6-31+G∗. The calculated molecular descriptors such as the EHOMO (eV), ELUMO (eV), band gap (eV), chemical hardness (η), global nucleophilicity, dipole moment (Debye), chemical potential, log P, molecular weight (amu) and Ovality. The descriptors that describe anti-gastric cancer activity of the studied compounds were used for QSAR analysis using SPSS and Gretl software packages for multiple linear regression (MLR), XLSTAT for partial least square (PLS) and MATLAB for artificial neural network (ANN). The methods (MLR, PLS, and ANN) were predictive. Nevertheless, ANN performed better than MLR and PLS. More so, molecular docking study was executed on the studied compounds and gastric cancer cell line (PDB ID:4oum); the docking studies showed that 2-(1-(2-(3-benzyl-5-(benzylthio)-3H-[1,2,3]triazolo[4,5-d]pyrimidin-7-yl)hydrazono)ethyl)phenol (A22) having the lowest binding affinity (-8.40 kcal/mol); this was correlated to the observed inhibitory activity of the compound against gastric cancer. Thus, it showed better inhibition than other studied compounds. The amino acid residues that were involved in stabilizing A22 in the active site of the 4oum are: VAL-9, ALA-10, THR-49, ASN-48, PRO-47 and TYR-46. Also, a good relationship was observed between the calculated binding affinity and the observed inhibition concentration (IC50).