Studying the upper critical field (µ0Hc2) and its anisotropy of superconductors is of great importance because it can provide an unusual insight into the pair-breaking mechanism. Since Fe1+yTe1−xSex exhibits the high µ0Hc2 and small anisotropic superconductivity, it has attracted considerable attention. However, some issues related to µ0Hc2 are still unknown, including the effect of excess Fe content on µ0Hc2 behavior and the origin of the crossover of the µ0Hc2c - T and µ0Hc2ab - T curves. In this work, the value of µ0Hc2 of Fe1+yTe0.6Se0.4 single crystals with controlled amounts of excess Fe was obtained by resistivity measurements over a wide range of temperatures down to ∼1.5 K, and magnetic fields up to ∼60 T. The crossover of the µ0Hc2c - T and µ0Hc2ab - T curves was found to be independent of the excess Fe content. The angle dependence of µ0Hc2 was also checked. The µ0Hc2(θ) symmetry at higher temperature near Tc could be fitted by anisotropic G-L model, and novel fourfold symmetry of µ0Hc2 at lower temperature was found. Based on our spin-orientation-locking pairing model, the crossover behavior originates from the anisotropic spin-paramagnetic effect, and the novel four-fold symmetry of µ0Hc2 could be understood by the theoretical analysis.