The present invention relates to a method of manufacturing lithium hydroxide and a method of manufacturing lithium carbonate using the same. The method of manufacturing lithium hydroxide includes: preparation of a lithium phosphate aqueous solution including lithium phosphate particles; addition of a phosphate anion precipitation agent to the lithium phosphate aqueous solution; and precipitating a sparingly soluble phosphate compound through a reaction of cations of the phosphate anion precipitation agent with anions of the lithium phosphate.