Present work reports the development of a novel, one-pot protocol for the rapid synthesis of pyrazolopyrazoles. The structures of synthesized compounds are in agreement with IR, NMR, and MASS Spectral data. A series of 4,5- disubstituted-3-methyl-1,3a,4,5-tetrahydropyrazolo[3,4-c]-pyrazoles (IIIa-f) was prepared by the reaction between 2,4-dinitrophenyl hydrazine, 5-methyl-2,4-dihydro- 3H-pyrazol-3-one (II) and different aldehydes to microwave irradiation. Compound II was obtained by cyclization of ethylacetoacetateate (I) with hydrazine hydrate by stirring in absolute ethanol. Microwaves used to heat the reaction mixture in the step II of the proposed reaction. All the compounds were synthesized with good yield. All the synthesized compounds exhibited antibacterial and antifungal activities at various MIC levels. Compound IIIa showed good activity against Streptococcus Mutans .The zone of inhibition produced by this compound is more than that of standard used for Streptococcus mutans. It shows moderate activity against Staphylococcus aureus, Shigella dysenteriae and Escherichia coli. Compound IIIb showed good activity against Streptococcus mutans and moderate activity against Shigella dysenteriae, Escherichia coli and fungus Candida and Rhizopus. Compound IIId showed moderate activity against Escherichia coli. Compound IIIe showed moderate activity against Streptococcus mutans, Shigella dysenteriae and Rhizopus and good activity against Candida. Compound IIIf showed good activity against Staphylococcus aureus, Candida and Rhizopus and moderate activity against Shigella dysenteriae.