Abadox: The Deadly Inner War (アバドックス, Abadokkusu) is a video game for the Nintendo Entertainment System published in Japan in 1989 by Natsume and North America in 1990 by the Milton Bradley Company.

It is a horizontally scrolling shooter in the vein of Gradius and R-Type taking place inside the intestinal tract of a giant alien organism.

Abadox has a high difficulty, and it takes one hit from an enemy projectile to be killed and restart from a checkpoint passed before death.

Second Lieutenant Nazal, the only surviving fighter of the galactic fleet, attempts to enter Parasitis's body and rescue Princess Maria before it is too late.

Power-ups include speed boosters, increased firepower, homing missiles and shields similar to the "Option" featured in Gradius.