Neuromorphic computing emulating the human brain offers a promising alternative to the Von Neumann architecture. Developing artificial synapses is essential for implementing hardware neuromorphic systems. Indium-gallium-zinc oxide (IGZO)-based synaptic transistors using charge trapping have advantages, such as low-temperature process and complementary metal-oxide-semiconductor compatibility. However, these devices face challenges of low charge de-trapping efficiency and insufficient retention. Here, IGZO synaptic transistors are introduced utilizing an indium-tin oxide (ITO) floating gate (FG) to overcome these limitations. The ITO FG's higher conductivity and alleviated chemical interactions with the Al