We reported a magnetically recyclable oleic acid modified NiFe2O4 (OA-NiFe2O4) nanocatalyst via an economical solvothermal approach for catalytic aquathermolysis of Liaohe heavy oil. Under the set conditions (240 degrees C, 3 MPa, 24 h), 9.67% of the heavy components can be effectively converted to light components, leading to a satisfactory viscosity reduction rate of 87.5%. After 5 cycles, OA-NiFe2O4 could still maintain impressive catalytic efficiency to implement high viscosity reduction rate of beyond 80.0%. Structural, spectral and morphological characterizations show that, oleic acid can be attached to the surfaces of NiFe2O4 nanoparticles coordinatively, which prevents the nanoparticles from being aggregated, resulting in both excellent catalytic aquathermolysis performance and recycling durability. Our work provides a low-cost and magnetically recyclable catalyst candidate for reducing the viscosity of heavy oil via catalytic aquathermolysis. (C) 2017 Elsevier Ltd. All rights reserved.