Abstract: In this paper, aiming at the problem of the lack of small energy impact test device for flexible composite materials in China, a low-cost double-duct drop hammer test device suitable for small energy impact test is designed and tested to meet the dynamic mechanical performance evaluation requirements of flexible composite materials under low energy impact load. Based on the modular design concept, this paper designs and manufactures an impact experimental device that integrates a hammer body with an adjustable mass of 0.5−5 kg, an impact height of 0−1000 mm, and a sharp or blunt hammer head. The impact energy range （3−50 J） can be accurately controlled by the formula E = mgh or an additional acceleration device, and it supports expansion to 100 J to meet a variety of test scenarios such as stab resistance to cutting or blunt impact. The performance test results show that the device has high stability （impact height error ±5 mm） in the energy range of 3−50 J, and the data repeatability is good, which has great reference value for relevant enterprises or researchers of flexible composite materials.