The performance of engineering consultants in designing the projects has the major role to determine the project’s success. In owner’s perspective, the quality of the products from engineering consultant within the certain time will contribute into the whole project performance. Owners must be able to identify several inhibiting factors of engineering consultant that will influence their performance. This research was conducted to identify several factors and their influence on the performance of the supervision consultant in the case of a project in specific company. This study belonged to a descriptive case study. Data of the study were collected by distributing questionnaires to the managements and engineers in a specific company. In total there were 30 respondents randomly selected to get involved in the study. The method used for this SEM PLS with three times iteration. The results of the study indicated there are several inhibiting factors of the engineering consultant, that simultaneously affect the implementation quality of their design. The factors of design consultants inhibiting factors, especially in specific projects where HR indicators lack continuous internal team communication (1.937), while in area of the consistency of job definition, the most influential are the occurrence of design errors which have an impact on rework (2.396). Another factor in coordination and communication between stakeholders’ areas is the absence of good coordination in empowering consultant personnel across expertise divisions (3.887). © The Author(s), under exclusive license to Springer Nature Switzerland AG 2026.