Google has recently launched a newer version of TensorFlow r0.12 which include support of Windows both CPU and GPU version can now be installed using Python >=3.5.2 (only 64-bit) version.
For CPU only version open command prompt and enter follow command
pip install --upgrade https://storage.googleapis.com/tensorflow/windows/cpu/tensorflow-0.12.0rc0-cp35-cp35m-win_amd64.whl
Follow this TensorFlow on Windows for step-by-step instructions.
UPDATE
To install current latest version please run following command:
pip install tensorflow #CPU only
pip install tensorflow-gpu #For GPU support
UPDATE 2020
TensorFlow 2.0 now has a single package for both CPU and GPU version, simply run
pip install tensorflow
If you’re using Anaconda you can install TensorFlow GPU version and all of its dependencies (CUDA, cuDNN) by running:
conda install -c tensorflow-gpu