Two plots in Fluvo-aquic soil (Endorusti-Ustic Cambosols) region were sampled with different grids sizes, Plot 1 (sandy loam, 1 m×1 m) with grid size of 10 cm×10 cm and Plot 2 (loamy clay, 30 m×18 m) with grid size of 2 m×2 m. Soil samples were extracted with DTPA and analyzed with flame atomic absorption spectrometry for Cu, Zn, Pb and Mn contents. Results indicated that variation coefficients (CV) of 4 elements ranged from 0.224 to 0.759. Mean contents and CV of 4 elements in Plot 1 were all higher than those in Plot 2, with Zn having maximum CV in Plot 1. Geostatistic results showed that all 4 elements had higher values of nugget and nugget/sill in Plot 1 than in Plot 2 and Pb of Plot 2 had maximum values, followed by Mn. Pb was affected most by random factors in both plots. Most isoline parts were approximately parallel with crop rows in both plots, especially Pb, Cu and Mn. It suggested that sampling grid size of 2 m×2 m was better in indicating effect of random factors on spatial distribution of heavy metals than 10 cm×10 cm in Fluvo-aquic soil region. Spatial distribution of heavy metals in Fluvo-aquic soil was also affected by soil texture, tilth activity, element type, and other land management practice.