PROBLEM TO BE SOLVED: To provide a medical tube seal device capable of smoothly performing seal welding and suppressing occurrence of a sealing defect even if a tube has folding tendency and the like.SOLUTION: A medical tube seal device 1 includes a plurality of tube seal parts 20A-20H that are disposed at a front face of a body part 10 and arranged in a right-left direction of the body part 10. Tube seal parts 20D and 20E of the plurality of tube seal parts 20A-20H are arranged near a center in the right-left direction of the body part 10, and disposed so that a position of a pair of electrodes is higher than that of the other tube seal parts.