This paper proposes a novel uncoded digital modulation scheme with high spectral and power efficiency, denominated 32P-3D. This scheme has a symbol constellation that consists of 32 points symmetrically distributed in a threedimensional space. The theoretical analysis and the simulations show a considerably high performance against the noise in comparison to 16-ary Quadrature Amplitude Modulation (16-QAM) in an Additive White Gaussian Noise (AWGN) channel. This paper presents a mathematical description of the proposed scheme, as well as a theoretical analysis of performance, which ratifies the simulation results.