The invention relates to a method for producing alkoxyphenol from hydroxyphenol, comprising an O-alkylation reaction of at least one hydroxyphenol into at least one alkoxyphenol, said reaction being carried out using an O-alkylating agent, an aqueous solvent containing a Bröensted base, and an organic solvent, with a base/O-alkylating agent ratio of between 0.5 and 1.5 in moles of base per mole of O-alkylating agent, an O-alkylating agent/hydroxyphenol ratio of between 0.5 and 2 moles of O-alkylating agent per mole of hydroxyphenol, and an organic solvent/hydroxyphenol ratio of less than 280 mL, preferably between 10 and 250 mL and more preferably still between 50 and 150 mL of organic solvent per mole of hydroxyphenol. The invention also relates to a method for producing at least one alkoxy-hydroxybenzaldehyde from at least one hydroxyphenol compound.