**Abstract**

Prior research looked at the impact of external audit quality (EAQ) on financial performance (FP) subsequent to the certification of the financial statements, which means after the external auditor's choice (EAC). However, in this research, I chose the EAC as a proxy for the EAQ to study the results of the EAC quality before the external auditor (EA) appointment on FP in the most well-known bank types, namely conventional and Islamic banks. This paper aims to minimize the EAC problem, overcome the choice risks, and solve the choice ambiguity between conventional and Islamic banks that exists in the literature. The first datum was collected from 180 conventional banks (CBs), while the second datum was composed from 180 Islamic banks (IBs). By using random and fixed effects, we investigated cylindrical panel data to parse the link between EAC quality and FP during the period (2010–2022). Hence, we inferred that the EAC quality ameliorated the IBs' FP but lowered that of the CBs.

**Keywords:** conventional banks (CBs), Islamic banks (IBs), external auditor (EA), external auditor choice (EAC), external audit quality (EAQ), financial performance (FP), agency theory, comparative study
