Hysteresis loops of melt-spun Nd₁₃Fe₇₇B₁₀ cooled down at remanent state were measured at 4.2 K and 250 K. The hysteresis loops were analysed on the basis of the Stoner-Wohlfarth (S-W) model, the inter-grain exchange coupled single domain (SD) model and micromagnetism. The coercivity higher than that predicted from the S-W model and the striking shift of the thin minor loop along the H-axix observed at the fields of H_max=4MA/m at 4.2 K indicated new evidences for the inter-grain exchange interaction . The S-W model failed in explaining the high _iH_c and the shift of the thin minor loop. The exchange coupled SD model was found to explain the experimental results qualitatively without difficulties associated with the S-W model. The micromagnetic calculations using a finite element technique simulated the experimental results fairly well quntitatively.