将激光诱导击穿光谱（LIBS）技术应用于复合肥样品中N，P和K元素含量的同步测量。选用10个已知样品作为定标样品，使用偏最小二乘法(PLS)分别建立各个元素定量分析的回归模型；然后使用5个待测样品检验这些模型的定量分析结果，并将预测结果与电感耦合等离子体发射光谱法测得的参考含量作对比。结果表明，激光诱导击穿光谱技术能够同时检测出5个待测样品的N，P和K元素的含量，待测结果的平均相对误差（REP）小于8%质量分数，平均相对标准偏差小于7%质量分数，检测极限值分别为0.16%，0.21%和0.50%质量分数。实验验证了LIBS技术同步快速准确测量复合肥中三大营养元素的能力。

The laser induced breakdown spectroscopy (LIBS) has been used to synchronized detection the concentration of nitrogen, phosphorus, potassium in compound fertilizers. Applied the partial least squares (PLS) method on 10 selected samples which are known as the calibration samples to establish quantitative analysis regression models of different components. Then, use 5 untested samples to test the result of quantitative analysis regression models. Finally compare the predictive value with the reference obtained by the conventional inductively coupled plasma atomic emission spectrometry (ICP-AES) method. The result shows that the average relative errors (REP) are less than 8% mass fraction. The relative standard deviation (RSD) is less than 7% mass fraction. The detection limits (LOD) are 0.16%, 0.21% and 0.50% mass fraction. The experimental verify the applicability of the laser induced breakdown spectroscopy in synchronization rapid and accurate measurement of the three major fertilizer nutrients.