Muscular System Diagram
Free printable muscular system diagram — a labeled illustration of the major muscles: deltoid, pectorals, biceps, triceps, abdominals, quadriceps and more. Download PDF or PNG for Letter paper.
The major muscles of the body
The muscular system is made of muscles that move the body and hold it upright. Here is what happens at each labeled part of the diagram:
| Muscle | What it does |
|---|---|
| Deltoid | The shoulder muscle that lifts the arm. |
| Pectorals | The chest muscles used to push and move the arms. |
| Biceps | The front upper-arm muscle that bends the elbow. |
| Triceps | The back upper-arm muscle that straightens the elbow. |
| Abdominals | The stomach muscles that support the body and help it bend. |
| Quadriceps | The front thigh muscles that straighten the knee. |
| Hamstrings | The back thigh muscles that bend the knee. |
| Gastrocnemius | The calf muscle used to point the foot and walk. |
Companion worksheet
A free fill-in worksheet with an answer key, built from the labels above — students match each muscle to its description, then answer a couple of short questions. Great for a quick check after using the diagram.
How to print
Choose Download PDF for a ready-to-print file that fits US Letter paper (8.5 × 11") in landscape, or Download PNG for the high-resolution image.
Frequently asked questions
How many muscles are in the human body?
The human body has more than 600 muscles.
What do muscles do?
Muscles pull on bones to move the body, hold you upright, and power automatic jobs like your heartbeat.
What paper size should I print this on?
The diagram is sized for standard US Letter paper (8.5 × 11") in landscape orientation. Use "Download PDF" for a print-ready file that fits the page automatically.