When an inspection apparatus of a semiconductor device repeatedly executes computation of prescribed area data, such as image processing for detecting defects, procedures for commanding, data load, computation, and data store need to be repeated the number of times of the computation. This may impose a limitation on the speeding up of the operation. In addition, when performing parallel computation by a high-capacity image processing system for handling minute images, a lot of processors are needed, resulting in an increase in cost. In order to solve the above-mentioned problems, in the invention, an inspection apparatus of a semiconductor device includes a data memory including an access section which is capable of reading and writing simultaneously, a plurality of numerical computation units, a connector for connecting the data memory and the numerical computation units, a controller for collectively controlling the contents of processing by the plurality of numerical computation units, another connector for connecting the numerical computation units and the controller, and a data transfer controller for controlling data transfer between the numerical computation units.