International Journal of Academic Multidisciplinary Research (IJAMR)   Year: 2019 | Volume: 3 | Issue: 10 | Page No.: 65-76 The Impact of Internal Audit on Improvement of Quality System According to Requirements for Performance Competence of Calibration and Testing Laboratories ISO: IEC 17025:2005 in National Leather Technology Center and Sudanese Standards and Metrology Organ Tayseer Elamin Mohamed Elfaki, Rabab Mustafa Talha, Ammar M. S. Abdalla Abstract: The study aimed to determine the impact of the internal audit on improvement of the quality system according to requirements for performance competence of calibration and testing laboratories ISO/IEC17025:20005. The study was conducted at National Leather Technology Center (NLTC) and Sudanese Standards and Metrology Organization (SSMO) in Khartoum State- Sudan, during the period from August 2018 to August 2019. A questionnaire was used as data collection tool. Thirty questionnaires were distributed to all laboratories employees in NLTC and SSMO, 26 of the laboratory employees had respond with percentage of (87%), while 4 had not respond. The data were analyzed using the statistical package for the social sciences (SPSS); the methodology used was the descriptive correlation. The study showed that (65.9%) respondents agreed that there was a relationship between the application of internal audit methodology and the application of the quality management system according to requirements for performance competence of calibration and testing laboratories ISO/IEC17025:2005. Also, the study indicated that (56%) respondents agreed that there was relationship between the application of internal audit methodology and number of cases of non-conformity of the quality system according to requirements for performance competence of calibration and testing laboratories ISO/IEC17025:2005, and readiness for accreditation. Also, the study showed that (54.6%) of them agreed that there was relationship between the application of the internal audit methodology and the continuous improvement of the quality system and increase customer satisfaction. So, the study concluded that all three hypothesis were fulfilled.