35Cl nuclear magnetic resonance (NMR) and relaxation measurements have been performed in stacked Sr2CuO2Cl2 single crystals with Néel temperature TN=257 K for two crystal orientations with respect to the applied field: H‖c and H⊥c. All the parameters of 35Cl NMR are found to exhibit a strong orientation dependence varying in temperature. In particular, the unconventional anisotropy and strong temperature dependence of the 35Cl nuclear spin–spin relaxation rate, T-12, are presented and discussed in terms of a crossover of the Cu2+ spin dynamics from Heisenberg to XY‐like correlation for T→T+N. The onset of anisotropic broadening and shift of the 35Cl NMR line was observed well above TN, which is in agreement with the previous results. © 1996 American Institute of Physics.