The effectiveness of a therapist-supported Internet intervention program for tinnitus distress in an industrial setting was evaluated using a cluster randomised design. Fifty-six Australian employees of two industrial organisations were randomly assigned, based on their work site (18 work sites from BP Australia and five from BHP Billiton), to either a cognitive behavioural therapy (CBT) program or an information-only control program. Participants were assessed at pre- and post-program, measuring tinnitus distress, depression, anxiety, stress, quality of life, and occupational health. The CBT program was not found to be superior to the information program for treating tinnitus distress. A high attrition rate and small sample size limit the generalisability of the findings, and further developments of the program and assessment process are needed to enhance engagement and compliance.