Neuronal growth inhibitory factor(GIF), a brain-specific member of metallothionein family named metallothionein-Ⅲ (MT-Ⅲ), is first validated to be capable of inhibiting the growth of neuronal cell in nervous system. GIF’s amino acid sequence, structure and metal-binding properties are like other metallothioneins’, and its gene shows strikingly high homology to other metallothionein-encoding genes, but they adopt different gene-regulation approaches. With its β-domain CPCP-loop, GIF may bind to some correlative factors that lie in brain extracts to display its specific physiological function. It is considered that GIF is markedly reduced in the brain of Alzheimer’s disease (AD) patients and in several other neurodegenerative disease.