A testing apparatus, comprising: an imaging part capturing, in time series, a first fine particle image of a well that holds a liquid containing fine particles; an image processor executing a first image processing which includes a process of generating a second fine particle image by extracting a contour of the first fine particle image, a process of performing a logical AND operation between the first fine particle image and the second fine particle image, a process of calculating a feature amount of the fine particles based on a result of the logical AND operation, and a process of determining growth of the fine particles in the well based on the calculated feature amount; and an output part outputting a result of the determination, wherein the image processor is switching between the first image processing and a second image processing according to a type of the fine particles to perform image processing on the first fine particle image, calculating a feature amount of the fine particles, and determining whether the fine particles grow or the growth is suppressed based on the feature amount; wherein the second image processing includes a process of generating a second fine particle image by performing first luminance value adjustment processing of enhancing a difference in brightness of an image with respect to the first fine particle image to adjust contrast and then extracting a contour of the contrast-adjusted first fine particle image, a process of performing a logical AND operation between the first fine particle image and the second fine particle image, and a process of calculating a feature amount of the fine particles based on a result of the logical AND operation, characterized in that: the image processor estimates the type of the fine particles by calculating a moving amount of the fine particles from the first fine particle image captured by the imaging part, and switches between the first image processing and the second image processing based on information on the type of the fine particles. an imaging part capturing, in time series, a first fine particle image of a well that holds a liquid containing fine particles; an image processor executing a first image processing which includes a process of generating a second fine particle image by extracting a contour of the first fine particle image, a process of performing a logical AND operation between the first fine particle image and the second fine particle image, a process of calculating a feature amount of the fine particles based on a result of the logical AND operation, and a process of determining growth of the fine particles in the well based on the calculated feature amount; and an output part outputting a result of the determination, wherein the image processor is switching between the first image processing and a second image processing according to a type of the fine particles to perform image processing on the first fine particle image, calculating a feature amount of the fine particles, and determining whether the fine particles grow or the growth is suppressed based on the feature amount; wherein the second image processing includes a process of generating a second fine particle image by performing first luminance value adjustment processing of enhancing a difference in brightness of an image with respect to the first fine particle image to adjust contrast and then extracting a contour of the contrast-adjusted first fine particle image, a process of performing a logical AND operation between the first fine particle image and the second fine particle image, and a process of calculating a feature amount of the fine particles based on a result of the logical AND operation, characterized in that: the image processor estimates the type of the fine particles by calculating a moving amount of the fine particles from the first fine particle image captured by the imaging part, and switches between the first image processing and the second image processing based on information on the type of the fine particles.