An oil-gas balancing apparatus includes: a body, a gas balancing opening and at least one oil balancing hole. The body has a first end and a second end opposite to the first end, and the first end can be fixedly connected to a shell of a compressor and in communication with an oil sump of the compressor and a chamber of the oil sump. The gas balancing opening is disposed on a first portion of an end surface of the second end. The at least one oil balancing hole is disposed on a second portion of the end surface of the second end. The second portion and the first portion are oppositely disposed. A compressor system can include the oil-gas balancing apparatus.