Mr. Marwick, who claims to have read more than twenty thousand palmas during a twenty-year career, adds that according to his reading, the Prince has "physical courage" and is an "adventurer".
He told Express.co.uk: "Harry follows in his mother's footsteps.
"Throughout Harry's life, he will always be dedicated to helping others and the needy, both individually and in groups.
"His hand shows, like some of the other hands of the Royals, that Harry can also contain his emotions at times, but he will give a lot to others."
Like his mother, Prince Harry is well known for his charitable activities, which include the founding of the charity Sentebale in 2006 to help children suffering from HIV / AIDS and the launch of the Invictus Games for service personnel injured.
Princess Diana was a prominent activist on behalf of the victims of HIV / AIDS, landmines and cancer.
However, according to Mr. Marwick, his mother also left a more physical mark on the Prince.
He explains: "In Harry's right hand there is a mark or a scar that shows, where he indicates that something significant happened and changed his life at a young age.
"It was probably the death of his mother."
Princess Diana died in a car accident in Paris on August 31, 1997, when Prince Harry was barely twelve years old.
Mr. Marwick detected other personality traits from the palm of Prince Harry's hand.
He said: "Harry's hand shows that he has physical courage, and possibly a small aggression at times.
"This shows that, although he will always return home, Harry can spend time away from home in other countries as an adventurer."
On the contrary, his older brother, Prince William, "will always appreciate being at home after returning from his travels."
Prince Harry served two tours of Afghanistan, in 2007-8 and 2012, although the first was interrupted after it was reported by foreign media.
He was the first Royal to serve in a conflict zone since Prince Andrew during the Falklands War.
Mr. Marwick also believes that he can determine the key points in the Prince's life from his palms.
He explains: "In Harry's hands, it shows that he really became independent at twenty, possibly around twenty-eight.
"This was perhaps an emotional moment for him when making decisions in his life regarding family, friends and relationships.
"There will be a significant change, which will affect Harry's life, which will take place in the late forties."
Mr. Marwick in a third generation palm reader, following the path established by his mother and grandfather.
In addition to his consulting work, he has made numerous media appearances, including on Sky TV and BBC Radio 4.