Cr3+ doped MgO was spectroscopical investigated. From the absorption spectrum, the crystal field and Racah parameters were determined, giving Dq = 1615cm-1, B = 586cm-1, and C = 3249 cm-1, thus Dq/B = 2.75 and C/B = 5.54. The emission covers the spectral region between 700nm - 1100nm, the emission lifetime at room temperature is 30μs. The peak emission cross section at 880nm was determined to be » 4´10^-20 cm2. Continuous wave laser oscillation of Cr3+:MgO at room temperature was realized under argon-ion laser pumping at 476nm. The free running laser wavelength was 840nm. Threshold pump power was 80mW, maximum output power was 20mW.