Anne Frank: She's the main character in this, as she is the one writing in the diary. She receives the diary for her 13th birthday prior to her family going into hiding. It is from these early writings that we see that she is full of ideas for her future, slightly naive about wars and what they are, and is often outspoken. Her intelligence and sensitivity are also evident in the way that she views those around her. Through her writing you can see her maturity developing, often more rapidly than it would have had she not been living under duress. She wrote many diaries, and revised them often.
Margot Frank: Margot wants to become a Nurse in Israel. She is more like her mother. Shy, quiet, dutiful. She loves Anne, but is also confused by Anne's dislike of their mother. She is shocked at some of Anne's thoughts and values.
Mrs. Frank: She is many years younger than Mr. Frank but has by all accounts been a very good and dutiful wife. She is also intelligent, but has remained a steady influence on the home front. She does not like all of the moving that they've had to make (first from Germany, and now hiding in Holland). She does not know, and was never told, that they could have left the country, or been given an easier assylum due to Mr. Frank's service in the First World War for Germany.
Mr. Frank: He is a warm and caring father, but is also a businessman. He makes some calculated risks which, in the end, do not pay off. He is tall, thin and slightly balding. He loves both of his daughters, but seems to indulge Anne more. As a result, many see Anne as spoiled. He and his daughter are very close and Anne will tell him things that she will not share with her mother or Margot. It is he that receives the diary after the war (from Miep Gies).
Mr. Van Daan (whose real last name was Van Pels) is a selfish man, addicted to nicotine and the finer things in life. He is ashamed of his son, and his wife, Augusta embarasses him. He does not feel that he has risen to the height of his potential yet and sees the war as a great imposition. He helped Mr. Frank when the Franks first arrived in Holland. He helped Otto find a job at Opeckta.
Mrs. Van Daan. She's very good at looking down on others. Bold, brash, loud, and pushy she likes others to see her fine things and to talk about how wealthy they are. She grew up in a wealthy family and one of her prized possessions is a fur coat that her father gave her.
Peter Van Daan. Peter is quiet, of average intelligence, and horribly embarassed by his parents. He likes to work with his hands and build things. He thinks that after the war he will work on a ranch or for a woodworker.
Of all of these characters, only Mr. Frank survives the end of the war.