Pyrazine Schiff base derivative N-［1-(pyrazin-2-yl)ethylidene］ isonicotinohydrazide(L) was obtained by the reaction of 2-acetylpyrazine and isoniazid in anhydrous ethanol. A coordination polymer {［Ag3L2(NO3)2］CH3CN}n was synthesized by diffusion method with the ligand and silver nitrate as raw materials, and its structure and properties were analyzed and characterized by X-ray single crystal diffraction, elemental analysis, IR, and fluorescence spectra. The results of single crystal diffraction analysis show that the complex belongs to monoclinic crystal system, P21/c space group, and the crystal cell parameters are a=0.611 70(10) nm, b=1.347 08(3) nm, c=2.018 69(4) nm, V=1.661 06(6) nm3, Z=2, Mr=970.19, Dc=1.940 g/cm3. The ligand molecules form a two-dimensional reticular structure with silver ions as the connecting point. Fluorescence spectrum analysis shows that both the ligand and the complex have better luminescent performance, and the fluorescence intensity of the complex is better than that of the ligand. The antibacterial activity indicates that the complex has good specificity to S. albus, S. luteus, and B. subtilis which has good prospects for medical application.