The ultrasound diagnostic apparatus, ultrasound image generation apparatus and method transmit ultrasound waves to a subject into which a puncture tool is inserted, receive reflected waves reflected from the subject and the puncture tool, and generate echo signals of time-sequential frames based on the received reflected waves, and generate an ultrasound image of the subject based on the generated echo signals. These apparatus and method generate a differential echo signal between time-sequential frames from the echo signals, perform a tip detection process based on the differential echo signal to thereby detect at least one tip candidate including a tip end of the puncture tool, highlight a tip candidate of the puncture tool detected to thereby generate a tip image, and display the tip image of the highlighted puncture tool so as to be superimposed on the generated ultrasound image.