A series of novel Schiff’s bases of Indazolone derivatives were prepared by the reaction of ohydrozinobenzoic acid with con HCl and it gives 1,2-dihydro-indazol-3-one. The 3-indazolone is react with 4 substituted aniline, it produces various derivative of schiff’s bases of Indazolone. The Indazolone derivatives synthesized were Ia, Ib ,Ic, Id, Ie, If, Ig and Ih. The structures of the synthesized compounds were confirmed by their IR,HNMR. All the synthesized compounds were tested for their antimicrobial activity against Gram+, Gram – bacteria. Among the synthesized compounds , the compounds Ia and Ih shown high anti bacterial activity against Staphylococus aureus(1mg/ml). Ib,Ic,Id,If and Ih exhibited high activity against Klebsiella aerogenes(0.5mg/ml). Ia , Ic and Ih possessed potent activity against E.coli(0.5mg/ml). The analgesic activity was determined by using hot plate method. The compounds Ib,Ig,Ih,(***p<0.001),Id and Ic (**p<0.01) possess significantly. The anti inflammatory activity was determined by Carragenan induced paw edema method. The compounds Ib ad Ig were found to exhibit high (***p<0.001) anti-inflammatory. Id and Ie were found to exhibit moderate (**p<0.01) anti inflammatory.