The solution-phase combinatorial synthesis of iminodiacetic acid triamide libraries linked to 1-(4-chlorobenzhydryl)piperazine has been reported. Ten mixture libraries, each containing 5 components, were synthesized in 4 steps from N-BOC-iminodiacetic acid anhydride. Antibradykinin effects of the mixture and individual libraries were compared using guinea-pig ileum smooth muscle. The changes in the inhibition were also observed by testing the combination of two different compounds from the same library. We found out the correlation between the inhibition of mixtures and that of individual libraries. It is possible to choose the mixtures with relatively high inhibitory effects to find out the most effective individual compound for further synthesis.