Microstructure and magnetocaloric properties have been investigated in a series of off-stoichiometric La2-xCexFe11Si2 (x = 0.2-1.2) magnetic refrigeration alloys. A complex multi-phase structure containing (La,Ce)(1)(Fe,Si)(13), La5Si3, (La,Ce)(2)(Fe,Si)(17), La1Fe1Si1\ and alpha-Fe phases was observed for Ce-doping alloys. Entropy change can be enhanced by the substitution of Ce for La, but higher Ce content (x > 0.8) leads to the decrease of magnetocaloric effect owing to the formation of (La,Ce)(2)(Fe,Si)(17) precipitates. The optimized composition of La1.2Ce0.8Fe11Si2 alloy exhibits a maximum entropy change of 21.8 J/kgK in 2 T, and a large volume change of 1.6% on the strong magnetoelastic coupled transition
