through a skyrmion, its twisted spins endow these electrons with an emergent electromagnetic field, yielding a variety of unconventional magnetoelectronic phenomena, such as topological Hall effect [12] and ultralow current density for skyrmion motion. [23][24][25][26] These properties together with the nanoscale size and topological stability, make magnetic skyrmion promising potential for future highdensity, low-power-consuming magnetic memory devices. [1][2][3] Like many quasiparticles in condensed matter physics, magnetic skyrmion also has a particle-like characteristic. [1][2][3] Owing to this feature, multiple skyrmions can aggregate and dissipate in a defined geometry, which holds promise for applications beyond conventional binary memories, such as multi-level memories, [1,28,29] neuromorphic computing, [28][29][30] probabilistic computing, [31] and nano-oscillators. [32,33] In previous work, the experiment demonstrated an accumulation and dissipation of isolated skyrmions in micrometer-sized geometries using the spin-polarized pulse current. [30] However, since the skyrmion-skyrmion interaction between different Magnetic skyrmions are topological swirling spin configurations that hold promise for building future magnetic memories and logic circuits. Skyrmionic devices typically rely on the electrical manipulation of a single skyrmion, but controllably manipulating a group of skyrmions can lead to more compact and memory-efficient devices. Here, an electric-field-driven cascading transition of skyrmion clusters in a nanostructured ferromagnetic/ferroelectric multiferroic heterostructure is reported, which allows a continuous multilevel transition of the number of skyrmions in a one-by-one manner. Most notably, the transition is non-volatile and reversible, which is crucial for multi-bit memory applications. Combined experiments and theoretical simulations reveal that the switching of skyrmion clusters is induced by the strain-mediated modification of both the interfacial Dzyaloshinskii-Moriya interaction and effective uniaxial anisotropy. The results not only open up a new direction for constructing low-power-consuming, non-volatile, and multi-bit skyrmionic devices, but also offer valuable insights into the fundamental physics underlying the voltage manipulation of skyrmion clusters.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adma.202107908.