How to create OO unit test checklist?

When you mean Unit Test(UT) checklist for an OOPs, are you speaking of the compiled executable or individual classes and source code?

The answer is:
A checklist before compilation is the only answer.

Your project management software should facilitate this.

Foremost your checklist should begin with the project and its contents.

1. Are the files current?
2. Are all the library files available?
3. All headers are available?
4. All source code is available and current?

4a. Is thesource code properly formatted to your departments specs? These specs should include mandatory header comment section listing developer, date, revision.
4b. All source code should be commented for legacy purposes! This defintely includes class definitions!!!i.e. events, methods, properties.
5. Reports containing Alpha test results prepared by the developer and QA.

5a. All modules in an OOPs should be pretested prior to inclusion in the project. This is the fundamental concept of OOPs as well as being a requirement. If it is not, it not reusable.
5b. How your project sub-classes it is up to your requirements and needs. This is a fundamental milestone in an OOPs project and is the first step in any successful endeavor. Complete documentation as stated above is the requirement.
I hope this helps a little.