Novel polymeric ligand by polycondensation of Schiff base with barbituric acid and formaldehyde in acidic medium was synthesized followed by synthesis of polychelates of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) ions. Structural and spectral properties were studied by elemental, spectral (FTIR, 1HNMR and UV–vis) and thermogravimetric analysis (TGA). Antimicrobial screening against Escherichia coli, Staphylococcus aureus, Bacillus subtilis, (bacteria) and Candida albicans, Microsporum canis, Cryptococcus neoformans (fungi) was done by agar well- diffusion method. Metal polychelates showed more effective antimicrobial nature as compared to the polymeric Schiff base. The elemental analysis data show the formation of 1:1 [M:L] metal polychelates. Thermal behavior of these metal polychelates was studied by TGA in a nitrogen atmosphere upto 800 °C. The comparative TGA data revealed that metal polychelates were more stable than their corresponding ligand. Polymeric Schiff base (AGB) acted as a tetradentate ligand and coordinated through azomethine nitrogen and oxygen of carboxylic acid groups. On basis of analytical data, six coordinated geometry was assigned for Mn(II), Co(II) and Ni(II) complexes and four coordinated for Cu(II) and Zn(II) complexes, which were further supported by FTIR spectra and TGA data. Owing to enhanced antimicrobial and thermal behavior, these polymers have wide range of applications such as thermally resistant, antimicrobial and antifouling coating materials.