Abstract: A series of novel 1-(pyridin-2-yl)hydrazines derivatives were synthesized from chloropyridine, hydrazine hydrate by nucleophilic substitution reactions. Their structures were characterized by ¹H NMR and ¹³C NMR techniques. The conversion rates of all kinds of chloropyridines were compared under the same reaction conditions. At last, the reason for low yileld of 1-(3-chloro-5-(trifluoromethyl)pyridin-2-yl)hydrazine was due to the formation of by-product 1-(5, 6-dichloropyridin-3 -yl)hydrazine.