Geometry structure, band structure, magnetic moment and magnetocrystalline anisotropy energy of layered 2HVSe(2) are investigated by first-principles calculations. It is found that the VSe2 is intrinsic ferromagnetic with an in-plane magnetocrystalline anisotropy no matter how the change of the strain and layer thickness is. Additionally, the valley splitting in monolayer VSe2 can be modulated by strain due to the modulated intrinsic exchange interaction of V 3d electrons. Interestingly, the valley splitting decreases and the V magnetic moment monotonously increases as a strain increases, showing that the valley splitting is related to the magnetic moment. Furthermore, the slight effect of interlayer coupling on V magnetic moment appears. The tunable magnetism and valley splitting may provide novel applications in multifunctional nanoelectronics.