Neuromorphic devices capable of emulating biological synaptic behaviors are crucial for implementing brain-like information processing and computing. Emerging 2D ferroelectric neuromorphic devices provide an effective means of updating synaptic weight aside from conventional electrical/optical modulations. Here, by further synergizing with an energy-efficient synaptic plasticity strategy, a multimodal mechano-photonic synaptic memory device based on 2D asymmetric ferroelectric heterostructure is presented, which can be modulated by external mechanical behavior and light illumination. By integrating the asymmetric ferroelectric heterostructured field-effect transistor and a triboelectric nanogenerator, the mechanical displacement-derived triboelectric potential is ready for gating, programming, and plasticizing the synaptic device, resulting in superior electrical properties of high on/off ratios (> 107), large storage windows (equivalent to ≈95 V), excellent charge retention capability (> 104 s), good endurance (> 103 cycles), and primary synaptic behaviors. Besides, optical illumination can effectively synergize with mechanoplasticity to implement multimodal spatiotemporally correlated dynamic logic. The demonstrated multimodal memory synapse provides a facile and promising strategy for multifunctional sensory memory, interactive neuromorphic devices, and future brain-like electronics embodying artificial intelligence.