Han-gyeol is a smart young man who hates to be tied down to one career in his life. Abhorring the idea of joining the family business, he is ordered by his grandmother to manage a cafe. Unable to disobey his grandmother, he reluctantly takes over the responsibility of running a cafe and begins to immerse himself in the gourmet coffee business. One day, he meets Eun-chan, whom he mistakes as a boy, and learns the meaning of true love...
Eun-chan supports her family by working two jobs; as Taekwondo instructor and food delivering girl. While making a delivery, she meets Han-gyeol. Han-gyeol is the grandson of chairwoman Bang of Dongin Foods, a company that has a thriving coffee business. Han-gyeol is a smart young man but he is fiercely independent and abhors the thought of being tied down by one career in his life. Sporting a short haircut, Eun-chan looks like a guy instead of a girl. After taking a shower and wearing a towel covering his private part, Han-gyeol meets Eun-chan for the first time. Meanwhile, Chairwoman Bang arranges blind dates for her grandson Han-gyeol to see him settle down.
Hyan Gyul still thinking she's a man, asks Eun Chan to pretend to be his "gay lover". She agrees to only show up on his blind dates, and he must buy her clothes and any time he touches her will be extra, [i]and[i] he has to give her an advance payment. Desperate he agreed. Eun Chan has feelings for Hyan Gyul's brother Han Sung, but then his ex-girlfriend Yu Ju returns and says she wants to get back together with him. Hyan Gyul's grandmother owns a coffee shop and she forces him to visit it with here, and then she reveals his new assignment.
Han Kyul is forced to take over the Coffee Prince shop by his grandmother, and he enlists Eun Chan's help.
It is the grand opening for Coffee Prince, but business is harder to bring in than they expected.
The Coffee Princes head out to the countryside for their first team-building retreat, but one more person learns of Eun Chan's secret.
Eun Chan goes on her first "date" with Han Sung. Han Kyul struggles with his unexpected feelings for Eun Chan.
Han Kyul fires Eun Chan, which affects them, and all of the other Princes, more than either of them care to admit.
Still confused, Han Kyul proposes that he and Eun Chan become sworn brothers.
Han Kyul and Eun Chan celebrate their momentary bliss of brotherhood, but it is quickly shattered.
As the Coffee Prince Concert quickly approaches, the relationships between Eun Chan and Han Kyul, and Yoo Joo and Han Sung begin to fall apart.
Eun Chan wishes to reveal her true identity. Yoo Joo receives an offer from the States that threatens her relationship with Han Sung.
Betrayed on all sides, Han Kyul hesitates on forgiving Eun Chan. Meanwhile, Yoo Joo prepares to leave for New York.
Han Kyul and Eun Chan enjoy the "honeymoon phase" of their relationship, despite their awareness that he might leave for the States in a month.
Eun Chan is introduced to Han Kyul's family as his new girlfriend. Yoo Joo tells Han Sung that she is expecting.
Yoo Joo and Han Sung's wedding makes Han Kyul more anxious to marry Eun Chan.
Han Kyul's grandmother is in the hospital, but that doesn't stop her from meddling in his relationship with Eun Chan.
Eun Chan leaves for Italy to study to become a barista for two years.