The Rock Island Police Department is divided into four divisions:

• Police Administration - oversees the management, plans, activities and operations of the entire police department, ensuring efficient and effective delivery of police services. 
• Field Operations - the uniformed patrol division of the Rock Island Police Department is responsible for promptly responding to emergency and non-emergency calls for service 24 hours a day.
• Criminal Investigations - the detective division of the Rock Island Police Department responsible for investigating felony crimes against persons or property, juvenile crimes and narcotics trafficking related offenses.
• Technical Services - responsible for all record keeping, including evidence retention, sex offender registration, fingerprinting services, abandoned vehicles, animal control, and traffic records.