What is known and objective Anecdotally, topical kunzea oil has been used to treat various skin conditions, including psoriasis and eczema, with good results. This study compared the clinical efficacy of kunzea oil (20%)-containing formulations in mild to moderate psoriasis. Methods A randomized, comparative, double-blind, 8-week study was undertaken. Thirty patients (age range: 25-74 years and mean ± SD: 52·8 ± 13·6 years) with mild to moderate psoriasis (affecting at least 10% of one or more body regions: arms, head, legs and trunk) randomly received ointment and/or scalp lotion containing 20% kunzea oil (test group) or control medications not containing kunzea oil (control group). Formulations in both treatment arms also contained 5% liquor carbonis detergens (LCD) and 3% salicylic acid. The clinical responses to the test and control formulations were evaluated using the Psoriasis Area and Severity Index (PASI). Results and discussion After 8 weeks of treatment, both test and control groups demonstrated a significant (P <0·05) improvement in PASI scores. Subjects in the test group had a decrease in mean±SD PASI score from 12·7 ± 7·9 to 6·7 ± 7·2, whereas the control group showed a decrease in PASI score from 8·1 ± 4·6 to 3·5 ± 4·7. Comparative efficacy analysis between the test and control groups did not reveal any significant difference (P > 0·05). What is new and conclusions The inclusion of kunzea oil made no difference to the efficacy of topical formulations containing LCD and salicylic acid for the treatment of psoriasis. Our study showed that both trialled treatment formulations were safe and effective in managing mild to moderate cases of psoriasis. However, the current results do not support the use of kunzea oil containing formulations for the management of psoriasis.