LDraw is a system of freeware tools and a 3D graphics file format standard for modeling Lego creations.

The LDraw file format and original program were written by James Jessiman in 1995, although the file format has since evolved and extended. He also modeled many of the original parts in the parts library, which is under continuous maintenance and extension by the LDraw community. As of March 2026 the library contains 16547 unique shapes or patterned parts, excluding shortcuts.

Following Jessiman's death in 1997, a variety of programs have been written that use the LDraw parts library, and file format. LDraw models are frequently rendered in POV-Ray or Blender, free 3D ray tracers.

In 2004, LDraw.org organization has been established, which main task is set to further develop LDraw file format and extend LDraw parts library. Organization is controlled by members of LDraw.org Steering Committee (SteerCo for short), elected by LDraw Organization Members. Core members of LDraw.org are in close ties with James Jessiman's family, which is the owner of the LDraw™ registered trademark. The LDraw.org Standards Committee (LSB for short) helms the development of the LDraw file format specifications.

Since 2001, LDraw.org project org's awards notable contributors with the James Jessiman Memorial Award.

Recipient is selected by LDraw.org Steering Committee, and approved after a consultation with Jessiman's family.

LDraw file format describes "part" (representation of Lego brick) as a set of geometric primitives ("p") in a form of polygonal triangulated mesh.

LDraw "models" consists of LDraw "parts", same way as Lego models consists of Lego bricks.