Abstract Sr 3Al 2O 6 was synthesized via citric acid precursor. The effects of the molar ratio of citric acid to total metal cations concentration (CA/M) on the formation of Sr 3Al 2O 6 were investigated. Increasing the CA/M promoted the formation of Sr 3Al 2O 6. Single-phase and well-crystallized Sr 3Al 2O 6 was obtained from the CA/M = 1, CA/M = 2 and CA/M = 4 precursor at temperature 1200 °C, 1100 °C and 900 °C, respectively. Differential thermal analysis and thermogravimetric (DTA/TG), X-ray diffractometry (XRD) and field emission scanning electron microscopy (FESEM) were used to characterize the precursors and the derived oxide powders. Sr 3Al 2O 6 nanoparticles with a diameter of about 50–70 nm were obtained.