The last years have seen a symbiosis of the fields of elementary particle physics and the astrophysics of the early universe. This text presents the background of the subjects and the latest developments at a level suitable for final year undergraduates and beginning graduate students. The first chapters cover the properties and interactions of elementary particles followed by discussion of the early universe, including inflation, dark matter and dark energy, and the growth of the galactic structure. The final chapters discuss cosmic rays and particle physics in the stars. The close relation...