This paper proposes a near-field Euler rotation-based technique to transform the far-field calculation of arbitrary conformal arrays into the pattern-multiplication form. Additionally, the calculation is greatly accelerated by a three-dimensional virtual equivalent source expansion (3-D VESE) technique and a layer-wise two-dimensional fast Fourier transform (2-D FFT) technique. Computational complexity analysis and several numerical examples validate the advantages of the proposed solution in terms of the efficiency and accuracy.