Objective To analyze whether there are new compounds in the decoction of Yiqi Tongluo formula, and study the acute toxicity of the whole formula. Methods Through high performance liquid chromatography(HPLC), compare the samples of Yiqi Tongluo formula with the mixed solution of separately decocted Urena lobata, Polygala arillata and Caulis Kadsurae, and analyze the differences of components; Study the acute toxicity of Yiqi Tongluo formula by examining LD50 and maximum dose experiment. Results 1. The three samples of Urena lobata, Polygala arillata and Caulis Kadsurae were tested by HPLC separately, the flow velocity was 1.0 mL/min, the column temperature was 30 ℃, and the wavelengths of 210 nm, 254 nm, 280 nm and 320 nm were detected respectively, the best absorption spectrum was 254 nm. 2. Mix the solutions of Urena lobata, Polygala arillata and Caulis Kadsurae in proportion, and compared with Yiqi Tongluo formula by HPLC in the wavelength of 254 nm. The positions and forms of the absorption peaks of the UV spectra in the two spectrogram were basically the same, except that the amplitudes of minority absorption peaks were slightly different, the fitting degree of the waveform was high. 3. No animal death and none obvious toxic reaction were found in the 8 concentration gradients of Yiqi Tongluo formula when determine LD50. 4. Yiqi Tongluo formula was dissolved to the maximum concentration, and the maximum intragastric dose was given at one time, as high as to 246.9 g/kg, also no animal death and obvious toxic reactions were seen. Conclusion: 1. Compared with the mixture of the Urena lobata, Polygala arillata and Caulis Kadsurae which were decocted separately, Yiqi Tongluo recipe had no significant changes in composition. 2. In the animal experiment of acute toxicity, Yiqi Tongluo formula has no obvious adverse reactions.