Gradients of 3D complex functional patterns at micro-scale are common in nature and used in numerous disciplines such as drug delivery, micro-fabrication, in vitro drug screening and tissue engineering. Here, we describe the use of temperature gradients to guide the phases of interfaced structures, which can be programmed by shape and composition into heterogeneous 3D complex structures. Using control over temperature and crosslinking as a driving mechanism, complex interfaced structures are built in a 3D gradient geometry. We demonstrate unique capabilities of temperature and crosslinking in the fabrication of soft systems dialling 3D gradients in materials properties, such as porosity, elastic modulus and bioactivity with broad applications in interfaced tissue engineering and drug delivery.