There are provided a next process-determining method capable of determining a next process to be carried out next objectively and at the same time in a short time period, as well as an inspecting method and apparatus which are capable of carrying out a predetermined inspection as to an object to be inspected according to the next process-determining method. A sample object is digitized to sample data formed by digital data. The sample data is compressed into compressed sample data according to a predetermined data format. There is calculated a difference data amount between a data amount of the compressed sample data and a data amount of reference data formed by digitizing and compressing a reference sample object in the same manner as the sample object is processed. Which of a plurality of predetermined numerical ranges the difference data amount belongs to is identified. A predetermined process is determined which is associated with the identified numerical range in advance as a next process to be carried out next.