Different derivatives of Cinnamaldehydes were prepared by Claisen-Schmidt condensation (by using Strong basic reagent). The prepared Cinnamaldehydes were treated with Hydrazine hydrate in presence of ZnO Nano-catalyst under microwave assisted solvent-free conditions to afford different substituted Pyrazoles. Green chemistry was employed. Comparisons of both microwave & conventional methods were studied & found that the first was more potent than the later. The synthesized compounds were characterized by FT-IR, 1HNMR & elemental analysis. All synthesized compounds were screened for in vitro test against EAC cell lines. Most compounds exhibited good inhibitor potency with IC50 values.