Abstract Background Thrombocytopenia is a marker of severity in dengue, and its resolution predicts clinical improvement. The objective was to evaluate mean platelet volume (MPV) trajectories as a predictor of platelet count (PC) recovery in dengue patients. Methods An observational, longitudinal and analytical study was conducted at Fundación Valle del Lili (Cali, Colombia). Patients diagnosed with dengue during 2016–2020 were included. The association between PC and the covariates was evaluated using simple linear, quadratic and non-parametric spline smoothing regression models. A longitudinal linear mixed model was adjusted and then validated for PC measurements. Results A total of 71 patients were included. The median age was 27 y, 38.5% were women and half had dengue with warning signs. A statistically significant PC decrease was observed when MPV was 13.87 fL and 4.46 d from the onset of symptoms, while PC displayed a significant constant increase with neutrophils count. Then, PC recovery was achieved with an MPV of 13.58 fL, 4.5 d from the onset of symptoms and a minimum neutrophils count of 150 μL. Conclusion MPV may be a predictor of PC recovery in dengue patients. PC recovery is expected when a patient has an MPV of 13.58 fL, an onset time of 4.5 d and a neutrophils count of 150 μL.