We report Ni addition induced changes in cationic distribution and its role in determining magnetic properties of Zn0.7-xNixMg0.2Cu0.1Fe2O4 (x = 0.0-0.7) nano ferrite synthesized by sol-gel auto-combustion method. X-ray diffraction demonstrates presence of cubic spinel phase, with crystallite size between 32.1-43.0 nm. Scanning electron microscope (SEM) images reveal modification of pore sizes. Saturation magnetization (M-s): 43.2-69.9 Am-2/kg and Neel magnetic moment (n(B)(N)):1.74-2.86 mu(B) increases up to x = 0.42, but at higher values of Ni content (0.42 < x <= 0.70) M-s and n(B)(N) decreases, accredited to migration of Fe3+ ions from A to B site or vice versa. With increasing Ni content, coercivity increases and range between 16.3-131.1 Oe. Zero values of Yafet-Kittel angle (alpha(Y-K)) suggest presence of Neel-type magnetic ordering in Zn0.7-x,NixMg0.2Cu0.1Fe2O4. Similar variation of bond angles (theta(B-B)(3), theta(B-B)(4)), M-s, n(B)(N) with Ni establishes the role of cationic distribution in determining magnetic properties. (C) 2017 Elsevier Ltd. All rights reserved.