Growth behaviors of InxGa1-xN (x ≤ 0.2) materials by plasma-assisted molecular beam epitaxy (PA-MBE) are investigated in detail. A precise control of the incorporation of indium into InxGa1-xN at a growth temperature of 580 ℃ is realized. The In0.19Ga0.81N shows a very narrow width of 587 arcsec for the (10.2) asymmetrical reflection from high-resolution X-ray diffraction and the background electronic concentration is 3.96× 1018 cm3. In the region of metal-rich growth, no negligible indium incorporation is observed even if the Ga beam flux is much larger than the equivalent N flux. This growth behavior might be ascribed to an incomplete Ga incorporation during InGaN growth. In addition, a slight increase of In flux results in crystalline quality degradation of InGaN epilayers.