A fully bioresorbable hybrid opto-electronic neural implant system was developed for simultaneous electrophysiological recording and optogenetic stimulation. The system, composed of biodegradable materials, features a flexible and soft design that allows direct optical and electrical interfaces with the curved cerebral cortex. It includes a biodegradable PLGA waveguide for optical stimulation and a Mo/Si bilayer electrode array for electrophysiological recording. The waveguide is optimized to minimize light transmission losses and photoelectric artifact interference, while the Mo/Si electrode prevents light absorption on the Si surface. The device was implanted in transgenic mice and successfully recorded local field potentials (LFPs) and performed optogenetic stimulation in the somatosensory area. The system biodegrades completely within 8 weeks, minimizing the need for secondary surgeries. The device demonstrated high biocompatibility, with no significant immune response or tissue damage. In vitro and in vivo tests confirmed its functionality, with the device recording ECoG signals and evoked LFPs during optogenetic stimulation. The system's performance was stable for 14 days, after which it degraded due to bioresorption and in vivo degradation of the PLGA waveguide. The device's biodegradable nature and ability to perform both recording and stimulation make it a promising solution for biomedical applications, offering a minimally invasive alternative to traditional implants. The system's integration of optogenetics and electrophysiology enables precise neural stimulation and real-time monitoring, with potential applications in treating neurological disorders such as epilepsy. The device's design and fabrication methods, including soft lithography and transfer printing, allow for scalable and cost-effective production. The system's ability to function for over two weeks and then biodegrade makes it a valuable tool for long-term neural monitoring and therapy. The study highlights the potential of bioresorbable implants in neuroscience, offering a sustainable and biocompatible solution for neural interfacing.A fully bioresorbable hybrid opto-electronic neural implant system was developed for simultaneous electrophysiological recording and optogenetic stimulation. The system, composed of biodegradable materials, features a flexible and soft design that allows direct optical and electrical interfaces with the curved cerebral cortex. It includes a biodegradable PLGA waveguide for optical stimulation and a Mo/Si bilayer electrode array for electrophysiological recording. The waveguide is optimized to minimize light transmission losses and photoelectric artifact interference, while the Mo/Si electrode prevents light absorption on the Si surface. The device was implanted in transgenic mice and successfully recorded local field potentials (LFPs) and performed optogenetic stimulation in the somatosensory area. The system biodegrades completely within 8 weeks, minimizing the need for secondary surgeries. The device demonstrated high biocompatibility, with no significant immune response or tissue damage. In vitro and in vivo tests confirmed its functionality, with the device recording ECoG signals and evoked LFPs during optogenetic stimulation. The system's performance was stable for 14 days, after which it degraded due to bioresorption and in vivo degradation of the PLGA waveguide. The device's biodegradable nature and ability to perform both recording and stimulation make it a promising solution for biomedical applications, offering a minimally invasive alternative to traditional implants. The system's integration of optogenetics and electrophysiology enables precise neural stimulation and real-time monitoring, with potential applications in treating neurological disorders such as epilepsy. The device's design and fabrication methods, including soft lithography and transfer printing, allow for scalable and cost-effective production. The system's ability to function for over two weeks and then biodegrade makes it a valuable tool for long-term neural monitoring and therapy. The study highlights the potential of bioresorbable implants in neuroscience, offering a sustainable and biocompatible solution for neural interfacing.