Non-neutral plasmas can excite many nonlinear plasma phenomena, including collisionless shocks, sheath layers, solitons, and plasma plumes. It is a fundamental issue in fields such as astrophysics, space physics, nuclear fusion, and plasma propulsion. Hybrid particle-in-cell (HPIC) methods are commonly used techniques for simulating non-neutral plasmas. However, the numerical methods for solving HPIC models of non-neutral plasma have some shortcomings. Here, a non-iterative convolutional method for solving the non-neutral HPIC model is proposed to address this problem. This method replaces Poisson’s equation in the non-neutral HPIC model with a convolutional equation.