Uranium manganese germanide, UMn₂Ge₂, crystallizes in body-centered tetragonal ThCr₂Si₂ structure with space group I4/mmm, a = 3.993Å and c = 10.809Å under ambient conditions. Energy dispersive X-ray diffraction was used to study the  compression behaviour of UMn₂Ge₂ in a diamond anvil cell. The sample was studied up to static pressure of 26 GPa and a reversible structural phase transition was observed at a pressure of ~16.1 GPa. Unit cell parameters were determined up to 12.4 GPa and the calculated cell volumes were found to be well reproduced by a Murnaghan equation of state with K₀ = 73.5 GPa and K' = 211.4. The structure of  the high pressure phase above 16.0 GPa is quite complicated with very broad  lines and could not be unambiguously determined with the available instrument resolution.