The 22-year-old singer was gunned down by a deranged fan following a concert performance in Orlando last month and her autopsy results have now been revealed.
According to E! New, the document states: "In consideration of the circumstances surrounding the death, and after examination of the body, toxicology analysis, and review of the available medical records it is my opinion that the death of Christina Grimmie, a 22-year-old white female witnessed to have been shot by another and subsequently transported to the hospital, is the result of a gunshot wounds of the head and chest. The manner of death is homicide."
Christina's brother Marcus tacked gunman Kevin James Loibl and was praised for preventing further injury or loss of life.
Earlier this month, her parents Tina and Bud and brother Marcus paid tribute to her "joyful heart and beautiful voice".
In a joint statement on a GoFundMe page, they said: "The outpouring of love and generosity that has been displayed to our family throughout these last few weeks has far exceeded anything we could have ever imagined.
"As we have always known, Christina's life was so very special, not only to us, but to everyone she touched with her joyful heart, beautiful voice and love for life and the Lord."
The family went on to thank those who had recognised the former 'Voice' contestant with donations and various other tributes, and confirmed they are discussing plans to "honour" her in future.
They added: "Words cannot express what the many memorials, donations and tributes shared by Christina's fans and those in the media and entertainment industry mean to us.
"She will live on in our hearts forever. We will take our time in determining the best ways to honor Christina moving forward. Thank you."
The GoFundMe page was launched by LH7 Management - which is operated by Christina's manager, Selena Gomez's stepfather Brian Teefey - to help the singer's family during their "time of need".