Log File structure

Hello. How can I analyse *.bin log file.
Where I can find description of log-file structure?

The header (beginning) of the file specifies how the binary data is to be decoded.
Take a look at the pymavlink dfreader file for more details.

If MATLAB is something you have in your workflow, then this .BIN to MATLAB converter may be of use to you: Ardupilog - A DataFlash log to MATLAB converter

Otherwise, as @amilcarlucas said, you’ll have to read the code to understand the format.
Basically, the dataflash logs are self-describing, meaning they start with FMT messages with define all other messages before the latter start appearing.

Best of luck!