Display system for excavating machine, excavating machine, and display method for excavating machine

A display system for an excavating machine, the display system being used for an excavating machine that can allow an upper swing body including a work implement having a bucket to swing about a predetermined swing central axis, the display system comprising:

• a vehicle state detecting unit that detects information about a current position and posture of the excavating machine;
• a storage unit that stores at least position information of a target plane indicating a target shape of a work object;
• and
• a processing unit that obtains, as target swing information, an amount of swing of the upper swing body including the work implement, based on information including a direction of a tooth edge of the bucket, information including a direction orthogonal to the target plane, and information including a direction of the swing central axis, and displays an image corresponding to the obtained target swing information, together with an image corresponding to the excavating machine and an image corresponding to the target plane, on a display apparatus, the amount of swing being required for the tooth edge of the bucket to become parallel to the target plane, and the direction of the tooth edge of the bucket being determined based on the information about the current position and posture of the excavating machine, wherein
• the processing unit makes a mode of the image corresponding to the target swing information displayed on a screen of the display apparatus different before and after the tooth edge of the bucket faces the target plane.