The invention relates to the field of medical detection and in particular to a blood aripiprazole therapeutic drug monitoring kit developed based on multi-dimensional online solid-phase extraction liquid chromatography analytical technology, more specifically to a method for accurately and quantitatively detecting aripiprazole drug concentration in blood by online solid-phase extraction and multi-dimensional liquid chromatography analytical technology. The kit includes a calibration reagent, a quality control reagent, a processing liquid, an extract liquid, a washing liquid, and an eluent. Thetherapeutic drug monitoring kit of the invention only needs to centrifuge a blood sample, achieves low repeated detection variability, high accuracy and stability, and low detection cost, has variousmethodological indicators that satisfy the requirement for monitoring the blood aripiprazole therapeutic drugs, and is easy to generalize.