Patterned composites with custom-tailored properties are essential for efficient thermal management required by the increasing integration and complexity of devices. In this work, a facile approach for the fabrication of functional, robust, and patterned composites was demonstrated using a simple and scalable laser engraving technique. Graphene patterns were incorporated into composites by the single- or multiple-lasing on poly(Ph-ddm) substrate. The resultant composites exhibited a high thermal conductivity (8.2 W/(m·K)) that was equivalent to an enhancement of 45 times compared to pure matrix. This increase was attributed to the formed high-quality graphene porous architecture, which established an effective heat conduction channel. With the merit of computer-aided design of the laser trajectory, the processing method offers the freedom to tailor the heat transfer pathway in composites. Besides, the composites presented the favorable Joule heating performance in terms of fast and stable response with the heating efficiency up to 276 °C‧cm2/W. More interestingly, the heaters with designable thermal patterns were also allowed, in which the electrical property of each heating unit could be tailored by adjusting laser parameters. This provides a unique opportunity to simulate the real case of non-uniform heat sources in many electronic devices, which will facilitate the design and development of heating dissipation systems. The material/process developed promises a wide range of possibilities for the efficient thermal management applications. Display omitted •Patterned functional composites are developed for efficient thermal management using a simple laser engraving technique.•The resultant composites have a high thermal conductivity (8.2 W/(m·K)) that is 45-fold higher than that of neat resin.•The processing method offers the freedom to tailor heat transfer pathways in composites.•Designable heaters are proposed to simulate the real case of non-uniform thermal distribution of electronic components.