Objective: To evaluate the 24-hour efficacy of tafluprost on the reduction of intraocular pressure (IOP)  in patients with primary open angle glaucoma (POAG) and ocular hypertension (OHT). Methods: In this  case-series study, a total of 43 eyes of 22 newly diagnosed patients with POAG and OHT from Shengyang  Aier Eye Hospital were enrolled. All patients were trained to use an Icare HOME tonometer to measure  IOP by themselves. For the certificated patients, aphysician used GAT to measure their IOP three times, and  then the patients used Icare HOME to measure 24-hour IOP by themselves. Patients was given tafluprost  once a day at 2100. Icare HOME was used by the patients themselves to measure 24-hour IOP again one month later. A one-way ANOVA and Bland-Altman analysis were used to compare the consistency  of the GAT used by a physician and the Icare HOME used by patients to measure IOP. A paired t test was  used to compare IOP at each time point, the mean, the peak, the valley and the fluctuation of 24-hour IOP  before and after treatment with tafluprost. Results: The mean IOPs measured with GAT by a physician and  Icare HOME by patients were 18.2±3.7 mmHg (1 mmHg=0.133 kPa) and 17.4±4.2 mmHg, respectively,  with no statistically significant difference (F=0.837, P=0.363). Bland-Altman analysis showed that there  was a good consistency between GAT measured by a physician and Icare HOME measured by patients.  IOP decreased at all time points of assessment after 1 month (all P<0.05). The range of IOP reduction at  different time points was 1.8 to 5.5 mmHg (all P<0.05). The mean, the peak, the valley, and the fluctuation  of IOP at baseline were 19.4±5.0, 25.0±5.8, 14.1±4.5 and 10.9±3.8 mmHg, respectively, and were reduced  to 15.6±4.2, 20.4±4.5, 11.3±3.6 and 9.2±2.9 mmHg after treatment (t=9.450, 9.636, 5.939, 3.137, all  P<0.05). Conclusions: Tafluprost provides effective 24-hour IOP reduction in newly diagnosed patients  with POAG and OHT.