The analysis of heavy metals in soil usually requires a complex procedure and digestion time if carried out by using traditional analytical techniques. In this paper,a moveable Laser-Induced Breakdown Spectroscopy (LIBS) instrument is established which is mainly equipped with a pulsed 1 064 nm Nd:YAG laser and a portable spectrometer,and has been applied for the quantitative measurement of Ba and Mn in soil. The intensity and relative standard deviations of the signal of Ba and Mn are carefully investigated by varying the way of data acquisition. Along with the experimental parameters optimization,a new data acquisition and processing method is used to improve the measurement precision and sensitivity. The calibration curves for quantitative measurement of Ba and Ma are derived. The measurement precisions,in terms of Relative Standard Deviations (RSD),are 9.0 % and 10.24% for Ba and Mn respectively. The Limits of Detection (LOD) for Ba and Mn in soil are improved to be 19.4 mg/kg and 115.4 mg/kg respectively,and are better than the results reported in literature.