The invention discloses a low-corrosion and low-formaldehyde-release polyformaldehyde composition and a preparation method and an application thereof. The composition includes copolymerized polyformaldehyde resin, an organic formaldehyde absorbent, an inorganic formaldehyde and formic acid absorbent, an antioxidant, a lubricant and a crystallization nucleating agent. The composition can be used in application occasions having extremely harsh requirements on the formaldehyde release amount and corrosivity, avoids the problems of discoloration, volatilization and emigration brought by a traditional formaldehyde absorbent, and besides, also has an excellent effect on absorbing formic acid; and the preparation method is simple and convenient to operate, and is quite easily applied to the polyformaldehyde technical field.