Garner, 43, died Thursday while an NYPD officer held him in a choke hold. A group of officers was attempting to arrest the father of six and grandfather of two for allegedly selling untaxed cigarettes.
In a video taken by witnesses, Garner can be heard telling officers "I can't breathe" before he goes still. The NYPD officially declared that Garner "died of a heart attack while being taken into custody."
Sharpton is meeting with Garner's family and the National Action Network on Saturday to hold a rally calling for an investigation into Garner's death.
The rally is scheduled for 9:30 a.m. and at 2 p.m. Sharpton will meet with the family and Staten Island community leaders at Mount Sinai Center for Community Enrichment in Staten Island.
"Rev. Al Sharpton has already spoken to both Mayor de Blasio and NYPD Commissioner Bratton about this tragedy and will work with them to ensure that justice is carried out," a post on the National Action Network website read.