A removal unit of methanol and acetone provided in a system including a production system of phenol having a decomposition reaction unit and a purification unit, and a production system of bisphenol A having a reaction unit and a concentration unit, the removal unit comprising: a removal column; a supply part provided in the midsection of the removal column; an overhead purge part in which methanol and acetone are removed; and a bottom recirculation part recirculated to the purification unit, wherein the supply part comprises a purification unit discharge part in which methanol, acetone, and water are included; and a concentration unit discharge part in which phenol, acetone, and water are included, wherein the purification unit discharge part comprises an aqueous layer discharge line through which the aqueous layer fraction in which methanol, acetone, and water are included flows from the separator, in the purification unit including: a first column for separating a reaction product discharged from the decomposition reaction unit into an acetone-rich fraction and a phenol-rich fraction; a second column connected to an acetone-rich discharge line, for purifying the acetone-rich fraction discharged from the overhead of the first column; and a separator connected to an acetone removal discharge line, for separating an acetone removal fraction discharged from the bottom of the second column into an aqueous layer fraction and an organic layer fraction, wherein the concentration unit discharge part comprises a water-rich discharge line through which a water-rich fraction in which phenol, acetone, and water are included flows from the acetone recovery column, in the concentration unit including: a dehydration column for removing unreacted acetone and water from a reaction product discharged from the reaction unit; and an acetone recovery column connected to an unreacted acetone discharge line discharged from an upper end of the dehydration column, for recovering acetone by removing the acetone from the water-rich fraction. a removal column; a supply part provided in the midsection of the removal column; an overhead purge part in which methanol and acetone are removed; and a bottom recirculation part recirculated to the purification unit, wherein the supply part comprises a purification unit discharge part in which methanol, acetone, and water are included; and a concentration unit discharge part in which phenol, acetone, and water are included, wherein the purification unit discharge part comprises an aqueous layer discharge line through which the aqueous layer fraction in which methanol, acetone, and water are included flows from the separator, in the purification unit including: a first column for separating a reaction product discharged from the decomposition reaction unit into an acetone-rich fraction and a phenol-rich fraction; a second column connected to an acetone-rich discharge line, for purifying the acetone-rich fraction discharged from the overhead of the first column; and a separator connected to an acetone removal discharge line, for separating an acetone removal fraction discharged from the bottom of the second column into an aqueous layer fraction and an organic layer fraction, wherein the concentration unit discharge part comprises a water-rich discharge line through which a water-rich fraction in which phenol, acetone, and water are included flows from the acetone recovery column, in the concentration unit including: a dehydration column for removing unreacted acetone and water from a reaction product discharged from the reaction unit; and an acetone recovery column connected to an unreacted acetone discharge line discharged from an upper end of the dehydration column, for recovering acetone by removing the acetone from the water-rich fraction. a first column for separating a reaction product discharged from the decomposition reaction unit into an acetone-rich fraction and a phenol-rich fraction; a second column connected to an acetone-rich discharge line, for purifying the acetone-rich fraction discharged from the overhead of the first column; and a separator connected to an acetone removal discharge line, for separating an acetone removal fraction discharged from the bottom of the second column into an aqueous layer fraction and an organic layer fraction, wherein the concentration unit discharge part comprises a water-rich discharge line through which a water-rich fraction in which phenol, acetone, and water are included flows from the acetone recovery column, in the concentration unit including: a dehydration column for removing unreacted acetone and water from a reaction product discharged from the reaction unit; and an acetone recovery column connected to an unreacted acetone discharge line discharged from an upper end of the dehydration column, for recovering acetone by removing the acetone from the water-rich fraction. a dehydration column for removing unreacted acetone and water from a reaction product discharged from the reaction unit; and an acetone recovery column connected to an unreacted acetone discharge line discharged from an upper end of the dehydration column, for recovering acetone by removing the acetone from the water-rich fraction.