Thanks for your answer.
Finally worked, I had to reinstall Qt with MSVC2010 and Android, and then all the other requirements for Android (SDK, Java SDK, NDK, Ant), after including corresponding paths to Android Option Tools, Kits were automatically detected.
Tried a "hello world" on an emulator and worked!!!
Now, I want to include OpenCV libraries in it, and am not able to find any steps to follow. I downloaded OpenCV for Android. How am I able to use it in a C++ Qt program for Android? Or alternatively use the C++ OpenCV precompiled ones?

Thanks in advance