A simple and efficient tandem route to novel spiro[indazolo[3,2-b]quinazolines has been developed. The reaction proceeds via in situ generation of the 1H-indazol-3-amines in ethanol followed by its reaction with the cyclic 1,3-dicarbonyls and isatin derivatives to assemble a novel N-fused polyheterocycles. The main advantages of this protocol include short reaction time, excellent yield, easy work-up, operational simplicity and the absence of extraction and chromatographic purification steps.