We developed a modular tube-shaped device as a proof of principle to enable the programmed release of encapsulated molecules for controlled drug delivery. Each drug-delivery tube module was prepared by assembling two separate silicone tubes in a series, one filled with a model compound (sodium fluorescein) and the other with a diffusional barrier material (polyethylene oxide, PEO). We varied the length of the PEO-filled tubes to control the release from the drug-delivery tube devices. The onset times and periods of drug release increased with the length of the PEO tube. To program the drug release, therefore, we prepared devices with combinations of drug-delivery tube modules with different lengths of PEO-filled tubes. Using PEO-filled tubes with very different lengths achieved a pulsatile drug release while a continuous drug release was realized by using PEO-filled tubes with small differences in length. We concluded that the modular combination of drug-delivery tubes, each composed of a diffusionbarrier tube of different length, demonstrates good potential for applications in programmed drug delivery.