The present study examined the preliminary efficacy and acceptability of a culturally modified therapist-guided Cognitive Behaviour Therapy (CBT) treatment for Arab Australians, aged 18 and over with symptoms of depression and anxiety. To facilitate ease of use, the treatment was delivered via the internet (internet CBT; iCBT). Eleven participants with at least mild symptoms of depression (Patient Health Questionnaire 9-item (PHQ-9) total scores ≥ 4) or anxiety (Generalised Anxiety Disorder 7-item (GAD-7) total scores ≥ 4) accessed the online Arab Wellbeing Course, which consisted of five online lessons delivered over eight weeks. Measures of depression, anxiety, distress and disability were gathered at pre-treatment, post-treatment and 3-month follow-up. Data was analysed using mixed linear model analyses. Ninety-one percent (10/11) of participants completed the five lessons over eight weeks, with 10/11 providing post-treatment and 3-month follow-up data. Participants improved significantly across all outcome measures, with large within-group effect sizes based on estimated marginal means (Cohen’s d) at post-treatment (d = 1.08 to 1.74) and 3-month follow-up (d = 1.53 to 2.00). The therapist spent an average of 90.72 minutes (SD = 28.98) in contact in total with participants during the trial. Participants rated the Arab Wellbeing Course as acceptable. Caution is needed in interpreting the results of the current study given the small sample size employed, raising questions about the impact of levels of acculturation and the absence of a control group. However, the results are encouraging and indicate that, with minor modifications, western psychological interventions have the potential to be of benefit to English speaking Arab immigrants.