In this work, we produced nanostructured tetragonal Cr₁₁Ge₁₉ by mechanical alloying after 15 hours of milling. The effect of pressures up to 7 GPa on its structure was studied through in situ angle-dispersive X-ray diffraction (ADXRD) measurements. The ADXRD patterns were analyzed using the Rietveld Method. The volume versus pressure data were fitted to a Birch-Murnaghan equation of state and the value of the bulk modulus B₀=128.42±5.61 GPa was obtained. Under high pressure a structural instability causes its decomposition. This instability was studied using the pair distribution function analysis.