To provide a blood-purification-treatment support system capable of making an accurate judgement of whether or not any treatment conditions for blood purification treatment should be changed. The blood-purification-treatment support system is capable of supporting blood purification treatment. The system includes a storage device that stores patient-specific patient data that are acquired on a plurality of days including at least no-treatment days on which blood purification treatment is not conducted, an estimating device that compares the patient data for the plurality of days stored in the storage device with one another and estimates a pre-treatment patient state regarding blood purification treatment, and a judging device that judges from the pre-treatment patient state estimated by the estimating device whether or not any treatment conditions for blood purification treatment should be changed.
