Using the TAM air isothermal microcalorimeter, the HFP-time curves of splenic lymphocytes growth were measured, and the effects of crude Radix Aconiti Lateralis and its processed products including Yanfuzi Danfupian, Baifupian on splenic lymphocytes growth were investigated. Some quantitative information, such as k, P-max etc. was obtained from the HFP-time curves. The results revealed that crude Radix Aconiti Lateralis and Yanfuzi had inhibitory effect on mice splenic lymphocytes growth: crude Radix Aconiti Lateralis with IC50 of 18 mg mL(-1) showed stronger inhibitory effect than Yanfuzi with IC50 of 32 mg mL(-1). Danfupian and Baifupian promoted splenic lymphocytes growth: Baifupian with EC50 of 25 mg mL(-1) showed a little stronger promotion effect than Danfupian with EC50 of 28 mg mL(-1). The result may be related to their toxicity and we could evaluate different bioeffects of crude Radix Aconiti Lateralis and its processed products on splenic lymphocytes growth from microcalorimetric measurement. (C) 2013 Elsevier B.V. All rights reserved.