The dissolution kinetics of lead-bearing ore in trichloroacetic acid (TCA) solution were investigated. The effects of various parameters were studied to optimize the dissolution conditions and to determine the leach kinetics. An increase in leaching time, temperature, and TCA concentration, and a decrease in particle size enhanced the conversion rate. The results show that 99.26% of lead content was extracted from the samples with particle size range of -90 + 75 mu m after 24 min leaching in 0.4 mol/L TCA at 800 rpm and 40 degrees C. The following expression based on the Jander (three-dimensional) model can be described: [1-(1-x)(1/3]2) = 22.36 x 10(-3) (C-TCA)(1.1516)(P)(0.55117)(r)(0.92609)exp (-20899/RT) t.