The Kissing Booth is teen romantic comedy film. It is about a late blooming teenager Elle Evans whose budding romance with a school senior and bad boy Noah and this makes her friend Noah's younger brother Lee.

Elle and Lee are thick friends from the day they are born because their mothers are very bonding. Elle's mother was very ill when she was at the age of 11 and passed away after 3 years. As they two grow up they loved dancing in the dance arcade machine. As she grew up, she had a huge crush on Noah but she tried very had to ignore him.

On the first day of junior year, Elle's uniform pant splits into two so she has to wear her freshman school skirt. She became the center of attention in the school. An older student Tuppen slaps her butt and Noah get in and fights Tuppen. Noah, Tuppen and Elle are served with detention. Tuppen apologies and ask her out while Elle accepts to date him. Unfortunately Tuppen des not show up because Noah made every one not to pursue Elle romantically.

For their school fundraiser, Elle and Lee came up with an idea of "Kissing Booth". During a party, Elle tells the popular OMG girls that Noah is the part of Kissing Booth. But Noah refused to be there. The Kissing Booth was crowded with the students until lee served to the kisser instead of Noah, all girls were disappointed. Rachel step up and kiss Lee. Lee and Rachel leave the Kissing Booth in the hands of Elle as they enjoy the fair.

Now the OMG girls decides to set up Elle to kiss the undesirable student but instead Noah kissed her. Elle opens her blindfold and see Noah in front of her and they started to kiss in front of every one. Noah offer her a ride on his bike but the rain forces them to stop. Elle kisses Noah and tells him that she cannot be another sexual conquest. Noah reveals that he has feelings for her.

Near the raucous beach party, Warren forces Elle to go for a hot tub. Noah comes to Elle's Defense. While Noah and Warren are fighting Elle ran away from the situation. Noah catches her up and give her a ride to home in between he apologies to her in the hollywood sign were they intimate for the first time. They establish their relationsip rules so that lee does not find out.

Noah tells Elle that he has been accepted to Harvard University.

While fixing Noah's bike, Elle falls and cut her face. Lee walks in the room while Noah treating her with band aid. Lee accuse Noah for hurting her and ask Elle is she dating him. Elle swear that nothing is going in between them. while Elle and Noah are kissing Lee came to know about the truth. Lee is very angry that Elle broke her friendship rules and took a car and left. Elle blames Noah for everything and went in search of Lee.

Lee totally ignored Elle. Suddenly she came up with the rule #7: “ No matter how mad you are at your best friend, you have to forgive them if they give you ice cream”. But it did not work. After some times he invites her to dance and they became friends again.

Elle goes to prom with Lee and Rachel. Noah emerges and confess his love for her publicly. He apologies to Lee and tell him that he will be leaving for Boston to get settle in the college.

At Elle and Lee's Birthday Party, Elle confess his love for Noah. Driving Lee's car she expresses her feeling for Noah with Lee, but the Batman suit was worn by Noah. Elle found out that Lee has invoked rule#18: “Always be happy for your bestie's success”.

Elle and Noah spent the following Week together before he leaves for college. Watching him go, She was unsure that if the relationship will last, but she knows a part of the heart will always belong to him and rides his bike into the sunset.

Thus the part 1 of The Kissing Booth ends.