Adherence to antihypertensive medications represents a crucial success factor for optimal blood pressure (BP) control in clinical practice. This study evaluated whether an additional pharmacist-led medication counseling could achieve better optimal BP control and enhance compliance. In a designated family clinic in a region with similar resident characteristics to Hong Kong, patients taking ≥ one antihypertensive agent with suboptimal compliance were randomly allocated to a brief 3-minute drug advice (control; n = 161) or pharmacist counseling (intervention; n = 113). The two groups were compared by repeated measure ANOVA at 3-months and 6-months with BP control and medication compliance as outcome variables, respectively. The proportions of patients having optimal compliance increased from 0% to 41.1% at 3 months and 61.9% at 6 months (P < 0.001). The proportion of patients having optimal BP control improved from 64.1% at baseline to 74.0% at 3 months and 74.5% at 6 months (P = 0.023). There were no significant differences between the two groups in the changes of BP control and compliance levels. This study implied that even a brief 3-minute drug advice might lead to improved BP levels among patients on antihypertensive medications in general practice, but did not demonstrate additional effects by pharmacist counseling.