Ce 3+ and Tb 3+ co-activated LaPO 4 nanowires (NWs) were synthesized by the hydrothermal method and studied in contrast to corresponding micrometer rods (MRs). The results indicate that electronic transition rate of Ce 3+ and Tb 3+ in NWs had only a little variation in comparison with that in MRs, and energy transfer (ET) rate and efficiency of Ce 3+ →Tb 3+ in NWs reduced. It is interesting to observe that the brightness for 5 D 4 – 7 F 5 of Tb 3+ via ET of Ce 3+ →Tb 3+ in NWs increased several times than that in MRs. This was attributed to the decreased energy loss in excited states being higher than 5 D 4 of Tb 3+ ions due to hindrance of boundary.