The reconstruction of the region of interest (ROI) by ultrasonic imaging is meaningful to obtain defect features, e. g. , shape, dimension and orientation. In this study, the full-mode total focusing method (FTFM) is proposed by using the strongest response signal among 21 views with different ray paths at each reconstructed point. The profile reconstruction and quantitative detection of unknown cracks are realized by signal acquisition with a set of phased array (PA) probe and wedge. A number of 4 mm length cracks with 25 mm central depth and different angles, e. g. , 0°, ±20°, ±50° and ±80°, are designed in the 40 mm thickness carbon steel specimens. Full matrix capture (FMC) is performed by using 45° wedge and 64-element linear array probe with a central frequency of 5 MHz to obtain FTFM images. The crack profiles are reconstructed intuitively by simulation and practical experiments. Measurement errors of crack length, orientation angle and central depth are no more than 0. 60 mm, 2. 39° and 0. 73 mm, respectively. Finally, appropriate parameters and position for PA probe are beneficial to achieve optimal FTFM image.