Antimatter does not have negative mass. In our universe, there is no such thing as negative mass. Mass only comes in positive form. ... Presumably, if negative mass existed, it would be repelled by objects with positive mass such as the earth or sun.

Is there anything with negative mass?

Physicists have created a fluid with "negative mass", which accelerates towards you when pushed. In the everyday world, when an object is pushed, it accelerates in the same direction as the force applied to it; this relationship is described by Isaac Newton's Second Law of Motion.

Does antimatter have a mass?

Antimatter particles share the same mass as their matter counterparts, but qualities such as electric charge are opposite. The positively charged positron, for example, is the antiparticle to the negatively charged electron.