Ferromagnetic and paramagnetic resonance has been observed with single crystals of europous oxide. The frequencies used were 23.8 and 27.5 Gc/sec, and the temperatures ranged from 1.5 to 300\ifmmode^\circ\else\textdegree\fi{}K. The linewidth increased from about 800 Oe at low temperatures to about 1400 Oe at room temperature. The low-temperature anisotropy field is given approximately by $\frac{{K}_{1}}{M}=\ensuremath{-}190$ Oe.