BACKGROUND: Kinesio taping is a commonly used intervention for patients with chronic low back pain. However, the medium term effects of kinesio taping in these patients are unknown. OBJECTIVE: To investigate the effectiveness of kinesio taping in patients with chronic low back pain after 6 months from randomization. METHODS: This was a randomized controlled trial with a 6 months follow up. One hundred and forty eight participants were randomly assigned to the experimental (kinesio taping with skin convolutions) or control (kinesio taping without convolutions-Sham Taping) group. Participants from both groups had the tape reapplied twice a week for four weeks. The outcomes were pain, disability and global impression of recovery after 6 months. RESULTS: One participant was lost to follow up in the experimental group (n=73, response rate 99%) and two in the control group (n=72, response rate 97%). After 6 months there were no statistically significant between-group differences in pain intensity (between-group difference -0.8 points, 95% CI -1.7 to 0.2), global impression of recovery (0.4, -0.7 to 1.5), or disability (-1.1, -3.0 to 0.7). CONCLUSION: Four weeks of kinesio taping treatment was no better than sham taping for patients with chronic low back pain, at 6 months follow-up. Trial Registration Number (http://www.ensaiosclinicos.gov.br/): RBR-7ggfkv (Brazilian Registry of Clinical Trials).