High Purity germanium (HPGe) detectors are found to be suitable for nuclear techniques for measuring radionuclides with very good energy resolution. Inter-comparison exercise is an important tool for external quality control that enables determination of the accuracy and uncertainty of detector measurement system. In this work, a comparative study of natural radioactivity in soil samples was conducted between the laboratory of Autorité nationale de Radioprotection et de Sûreté Nucléaire (ARSN), Burkina Faso and the laboratory of Radiation Protection Institute of Ghana Atomic Energy Commission (RPI-GAEC),Ghana to ascertain the reliability and accuracy of measurements made in Burkina Faso. For this purpose: Some replicate soil samples, assumed as proficiency test samples, were analyzed on both the High Purity Germanium detector of ARSN and RPI. The statistical performance indicators of z-score, precision, trueness and relative bias were used for the evaluation. The limit for acceptable precision and the maximum acceptable bias for all the radionuclides were set to 20% and 15% respectively.