A booster device for enhancing scent-emitting capability of an aroma display , wherein said aroma display has a columnar shape having first and second surfaces and a side surface, said first surface having an emitting opening for emitting a scent, and a wind source for emitting said scent to the outside of said aroma display is provided in said aroma display, maximum air flow generated by the wind source being equal to or smaller than a prescribed value; said booster device comprising: a housing detachably accommodating said aroma display therein; and a fan provided in said housing , maximum air flow generated by which is larger than said prescribed value; wherein said housing includes a cylindrical outer housing having a bottom surface with an air inlet for taking in air and a cap with an opening, and a holding member holding said aroma display in said housing such that said emitting opening of said aroma display faces said opening; said holding member holds said aroma display such that an air passage is formed between said outer housing and said aroma display; said fan is arranged in said housing to blow out air to said air passage ; and said cap has a narrowing member for narrowing the air flow generated by said fan, provided at an end portion of said outer housing on the side of said first surface of said aroma display . said aroma display has a columnar shape having first and second surfaces and a side surface, said first surface having an emitting opening for emitting a scent, and a wind source for emitting said scent to the outside of said aroma display is provided in said aroma display, maximum air flow generated by the wind source being equal to or smaller than a prescribed value; said booster device comprising: a housing detachably accommodating said aroma display therein; and a fan provided in said housing , maximum air flow generated by which is larger than said prescribed value; wherein said housing includes a cylindrical outer housing having a bottom surface with an air inlet for taking in air and a cap with an opening, and a holding member holding said aroma display in said housing such that said emitting opening of said aroma display faces said opening; said holding member holds said aroma display such that an air passage is formed between said outer housing and said aroma display; said fan is arranged in said housing to blow out air to said air passage ; and said cap has a narrowing member for narrowing the air flow generated by said fan, provided at an end portion of said outer housing on the side of said first surface of said aroma display . a housing detachably accommodating said aroma display therein; and a fan provided in said housing , maximum air flow generated by which is larger than said prescribed value; wherein said housing includes a cylindrical outer housing having a bottom surface with an air inlet for taking in air and a cap with an opening, and a holding member holding said aroma display in said housing such that said emitting opening of said aroma display faces said opening; said holding member holds said aroma display such that an air passage is formed between said outer housing and said aroma display; said fan is arranged in said housing to blow out air to said air passage ; and said cap has a narrowing member for narrowing the air flow generated by said fan, provided at an end portion of said outer housing on the side of said first surface of said aroma display . <EOS>