The Expert Infantryman Badge, or EIB, is a military badge of the United States Army. It is the non-combat equivalent to the Combat Infantryman Badge. The main difference between the two decorations is that the Combat Infantryman Badge (CIB) is awarded for participation in infantry ground combat, while the Expert Infantryman Badge is presented for completion of an approved Army training course.

The badge was first created in October 1943. It is awarded to U.S. Army personnel who hold infantry or special forces military occupational specialities. To be awarded the EIB, service members must complete a testing phase which is the culmination of weeks of training, leading to a final evaulation period. The EIB test is administered on the average once per year with pass rates averaging no more than 50 percent, depending on the unit conducting testing. Due to the rigid testing procedures, many holders of the EIB value it more than the CIB.

Personnel who have been awarded both the Expert Infantryman Badge and the CIB are not authorized to wear both decorations simultaneously. In such cases, the individual soldier may decide which to wear on the Army uniform.

A similar decoration exists for medical personnel, known as the Expert Field Medical Badge.