An ultrasound computed tomography diagnostic system comprising: a plurality of elements (E) configured to perform at least one of emission of ultrasound to a test object (T) and reception of reflected ultrasound that is ultrasound reflected from the test object (T); a data collection unit configured to collect measurement data of the reflected ultrasound through at least one of the plurality of elements (E) while switching an element that emits ultrasound; an image acquisition unit configured to perform steps of extracting, from the collected measurement data, partial measurement data corresponding to a point of interest, inputting the partial measurement data to a first learner , and acquiring pixel values of a partially reconstructed image output from the first learner , wherein the image acquisition unit is configured to repeatedly perform the steps for a plurality of points of interest included in a region of interest in order to reconstruct a tomographic image corresponding to the region of interest of the test object (T); an image display device configured to display said reconstructed tomographic image corresponding to the region of interest of the test object (T); and the first learner using a neural network, the first learner being configured to learn using training data including a test-object model and simulation measurement data and to output the partially reconstructed image from the partial measurement data which is input to the first learner , the test-object model being expressed by a distribution of acoustic features, the simulation measurement data being obtained by emitting ultrasound while switching an element that emits ultrasound and receiving reflected ultrasound from the test-object model using at least one of the plurality of elements (E) in a simulation space in which a size and an arrangement of the plurality of elements (E) are simulated. a plurality of elements (E) configured to perform at least one of emission of ultrasound to a test object (T) and reception of reflected ultrasound that is ultrasound reflected from the test object (T); a data collection unit configured to collect measurement data of the reflected ultrasound through at least one of the plurality of elements (E) while switching an element that emits ultrasound; an image acquisition unit configured to perform steps of extracting, from the collected measurement data, partial measurement data corresponding to a point of interest, inputting the partial measurement data to a first learner , and acquiring pixel values of a partially reconstructed image output from the first learner , wherein the image acquisition unit is configured to repeatedly perform the steps for a plurality of points of interest included in a region of interest in order to reconstruct a tomographic image corresponding to the region of interest of the test object (T); an image display device configured to display said reconstructed tomographic image corresponding to the region of interest of the test object (T); and the first learner using a neural network, the first learner being configured to learn using training data including a test-object model and simulation measurement data and to output the partially reconstructed image from the partial measurement data which is input to the first learner , the test-object model being expressed by a distribution of acoustic features, the simulation measurement data being obtained by emitting ultrasound while switching an element that emits ultrasound and receiving reflected ultrasound from the test-object model using at least one of the plurality of elements (E) in a simulation space in which a size and an arrangement of the plurality of elements (E) are simulated. <EOS>