Telmisartan (TEL), a type of antihypertensive drug, has poor solubility. To improve its solubility, the co-amorphous telmisartan with pimelic acid (PA) in molar ratio of 1:1 and 2:1, respectively, were obtained using a liquid-assisted grinding method. The co-amorphous system was characterized by the powder X-ray diffraction and differential scanning calorimetry. The molecular interactions of the co-amorphous were studied by the infrared spectra. After the formation of co-amorphous, the solubility of TELwas much improved, and the apparent solubility values were approximately 9-15 times as high as that of crystalline TEL. Moreover, the co-amorphous TEL-PA was stored under 25 °C/20% RH for a month without any evidence of conversion by powder X-ray diffraction analysis.