The Rock Island Police Department is divided into four divisions:

• Field Operations Division - the uniformed patrol division of the Rock Island Police Department.
• Criminal Investigations Division - the detective division of the Rock Island Police Department responsible for investigating felony crimes against persons or property and juvenile crimes.
• Tactical Operations Division - this division encompasses the Tactical Operations Unit, Narcotics Unit and the Drug Enforcement Task Force Officer. 
• Technical Services Division - responsible for all record keeping, including evidence retention, sex offender registration, fingerprinting services, abandoned vehicles, animal control, and traffic records.