This page explains how to draw, edit, and style lines between diagram elements in Astah.
You’ll learn how to:


Draw lines

  1. Hover over the source object.
    The Draw Suggest icons appear near the object.
  2. Click the line type you want to draw.
  3. Click the target object to complete the connection.
    Draw lines

Cancel drawing: Press ESC or right-click.


Line style

Astah There are 4 line styles.

1. Line (Straight line)

A single straight segment.
Straight Line

2. Line (Right Angle)

A line made of one or more orthogonal (90°) segments.

Line with right angles

3. Curve

A smooth curved line.

Curved line


4. Curve (Right Angle)

A curved line that includes right-angle corners.

Curve right angle line


Default line style

Default styles vary by diagram type:

  • Data Flow Diagram: Curve
  • ER Diagram: Line (Right Angle)
  • All other diagrams: Line (Straight)

To change the line style while drawing, select a style from the diagram toolbar.
Default Line Style in Astah


Change line style

To change the style of an existing line:

  1. Right-click the line.
  2. Select the new style from Line style.
    Change Line Style

TIPS: Use shortcut keys
Switching styles is faster with shortcuts:
Line (Right Angle): Ctrl/⌘ + E
Line (Straight): Ctrl/⌘ + L


    Line Jumps

    Line jumps are available in Astah 8.2 and later.
    They are supported for Line (Straight) and Line (Right Angle) styles only.
    When enabled, Astah shows a visual cue at line intersections to improve readability.


    Change line jump style

    You can switch the jump appearance here:

    1. Tools → System Properties → Diagram Editor → Style
    2. Choose the jump style you prefer, then click Apply → OK.
      Line Jump Style Change

    Turn line jumps on/off

    1. Globally (all diagrams)

    1. Tools → System Properties → Diagram Editor → Style
    2. Turn Jump at line intersection (Only Line and Right Angle Line) on/off, then click Apply → OK.
      Turn on/off jump on diagrams

    2. Per diagram

    Right-click the diagram background and choose Line jump.

    Turn off line jump per diagram


    3. Per line

    Right-click the line and choose Line jump from the context menu.
    turn off/on jump line per line

    If you can’t click “Line jump”
    If the Line jump menu is disabled, line jumps are turned off in System Properties or for the current diagram. Enable both settings first.


    Moving a connecting point

    By default, lines connect to the center of an object.

    connecting-point.png

    To connect off-center:

    1. On the diagram toolbar, turn off Connect line to the center of the object. Connect line to the center of the object

    2. Drag the connecting point to the desired position on the object border.Connecting point

    This helps you avoid overlaps and keep diagrams readable.


    Jump to related model elements

    Since Astah version 8.5, you can jump from a line to its related model elements.

    1. Right-click on a line.
    2. Select Move to related element.
    3. Choose the element you want to open.
      Jump to ER Entity

    This is especially useful in diagrams with many overlapping elements.


    Shared Style (Generalization)

    Shared Style lets you bundle multiple Generalization lines into a shared trunk for a cleaner hierarchy.
    Generalization in shared style



    There are two ways to apply Shared Style:

    Option 1: From the Edit menu

    1. Select all Generalization lines you want to bundle.
    2. Choose Edit → Shared Style → Vertical.
      Shared Style

    Option 2: Drop onto an existing Generalization arrow

    1. Start drawing another Generalization line.
    2. Drop its target end onto the arrowhead of an existing Generalization. The lines merge into Shared Style automatically.
      Create Generalization in Shared Style in Action