A treadmill belt guard includes a weighted cylindrical body, a first arm, a second arm, a first adaptor, a second adaptor, a first interlocking fastener, and a second interlocking fastener. The first arm is externally connected onto a lateral surface of the weighted cylindrical body. The second arm is externally connected onto the lateral surface of the weighted cylindrical body. The first arm and the second arm are positioned parallel to each other. The first adaptor is terminally mounted to the first arm through the first interlocking fastener. The first arm is positioned in between the first adaptor and the weighted cylindrical body. The second adaptor is terminally mounted to the second arm through the second interlocking fastener. The second arm is positioned in between the second adaptor and the weighted cylindrical body.