Purpose: The present study assessed halitosis after treatment of gingivitis by using different diagnostic modalities. Materials and Methods: A total of 27 patients (47 ± 7 years old; 14 women, 13 men) diagnosed with chronic periodontitis underwent supragingival mechanical debridement (day 0). Measurement of volatile sulfur compounds (VSC), visual analogue scale (VAS) and organoleptic assessment, visible plaque index (VPI) and gingival bleeding index (GBI) were obtained at baseline (prior to treatment of gingivitis) and then after 30, 90, and 180 days. The Friedman test was used to compare outcome data at days 0, 30, 90, and 180. Post-hoc comparison (tongue cleaning and non-cleaning) was performed using the Student t test for VSC and VAS and the Mann-Whitney test for organoleptic measurements. The level of significance was set at 5%. Results: VSC and VAS means (days 0 and 180) were, respectively, 463.41 ppb (± 496.12 ppb) and 245.96 ppb (± 301.51 ppb) and 6.28 cm (± 2.23 cm) and 5.03 cm (± 2.01 cm). The frequency of high organoleptic scores (3 to 5) declined from 96.29% (day 0) to 81.48% (day 30), with a reduction of around 50% at day 180. Post-hoc comparison did not reveal any significant differences between the indicators analysed. Conclusion: Supragingival plaque control reduced halitosis in patients with periodontitis, but tongue cleaning vs no tongue cleaning did not yield different results. Keywords: gingivitis treatment, halitosis, supragingival plaque control