The concentration field was measured with various nozzle diameters, nozzle distances, and inlet flow rates in a submerged impinging stream mixer (SISM) using planar laser-induced fluorescence to obtain characteristic parameters such as correlation dimension, Kolmogorov entropy, and Lyapunov exponents that describe the chaos phenomenon and reflect the microcosmic mixture effect of a SISM by mean of the chaos theory. The chaotic characteristic parameters were influenced significantly by different nozzles distances, nozzle diameters, and inlet flow rates and their distributions followed a similar changing regularity by which all parameters decreased with larger nozzle diameter and increased with higher inlet flow rate.