@sakya I don't know which file to check with dependency walker.

I found the file qsqlmysql.dll in these directories
C:\Qt\Qt5.2.0\Tools\QtCreator\bin\plugins\sqldrive rs
C:\Qt\Qt5.2.0\5.2.0\mingw48_32\plugins\sqldrivers
C:\Qt\Qt5.2.0\5.2.0\mingw48_32\plugins\sqldrivers
and I added them to the environment PATH, I still have the same error

@ChrisW67 I downloaded and installed the connector, but with no hope