Software testing generally proceeds as follows: generating test-cases, selecting test-data, executing a test target program, inspecting execution result and evaluating whether testing has already been sufficient or not yet. As for methods for structural testing of programs, the way using a coverage, where the coverage means what extent given testing criteria are satisfied, is noted. At the evaluating step, whether or not we finish the testing is determined in view of the coverage. This paper proposes a testing method for structural testing of concurrent programs written in Ada programming language. The Event InterActions Graph(EIAG) is used as a model for concurrent programs. The EIAG consists of Event Graphs and Interactions. An Event Graph is a control flow graph of a program unit in a concurrent program. The Interactions represent interactions between the program units. Program units are such as procedures, functions and task-types. After generating test-cases on the EIAG, a method for selecting test-data is described and measures to cope with infeasible test-cases with which are generated in this step is clarified. And a forced execution of a test target concurrent program in order to solve the nondeterministic execution is investigated. The nondeterministic execution is characteristic of concurrent programs.