UML Use Case Diagram
Behavioral
A UML diagram of actors and the system functions they use.
Overview
Use case diagrams show who interacts with a system and which goals they pursue. Ovals are use cases. Stick figures are actors. The system boundary boxes the product. Use this page to copy a starter diagram into the studio. The long-form use case guide covers include, extend, and scope.
Keywords
Actor
Use Case
System Boundary
Include
Extend
Components
Key elements that make up this diagram type
Actor
A role outside the system, such as Customer or Admin.
Use case
A goal written as a verb phrase, such as Place order.
System boundary
A box that groups use cases that belong to the product.
Association
A line from an actor to a use case they initiate or participate in.
Where It's Used
Common applications and scenarios for this diagram
- •Inception and discovery
- •SRS and product briefs
- •Teaching UML to beginners
- •Aligning QA with user goals
Use Cases & Industries
Use Cases:
Product scoping
Requirements kickoff
Stakeholder workshops
Feature inventory
Industries:
Software Development
Product Management
Enterprise Applications
Education
How to Create with UML Diagram Studio
Step-by-step guide to create this diagram in our studio
1
Open the editor
Start from the free UML diagram tool on the homepage.
2
Declare actors and use cases
Use left/right actors and usecase aliases.
@startuml
left to right direction
actor Customer
actor Admin
rectangle "Shop" {
usecase "Browse catalog" as UC1
usecase "Place order" as UC2
}
Customer --> UC1
Customer --> UC2
@enduml3
Preview and export
Check that the boundary matches the product, then export.
Complete Example Code
Full PlantUML code example you can use in the studio
@startuml
left to right direction
actor Customer
actor Admin
rectangle "Online Shop" {
usecase "Browse catalog" as UC1
usecase "Place order" as UC2
usecase "Manage products" as UC3
}
Customer --> UC1
Customer --> UC2
Admin --> UC3
@endumlBest Practices
- ✓Write use cases as user goals, not UI screens
- ✓Keep one system boundary per product
- ✓Do not dump every feature on one diagram
- ✓Link each use case to a sequence or activity later
Explore More
Discover other diagram types and resources
Related Diagrams
Other diagram types you might find useful
Activity Diagram - steps inside a use case
Sequence Diagram - messages for a scenario
Class Diagram - domain structure behind the features