There are two systems of calligraphy in Han dynasty, one is inscriptions, the other is bamboo slips and ink marks, which are books and documents before paper was invented or widely used. Because of different materials, different writing tools, different contents, different shapes and different writers' identities, they show different artistic styles. The written content of Han bamboo slips is either correspondence notes or official document reports, so most of them are informal and hasty. Han bamboo slips are limited by narrow faces and small characters. However, the layout of the composition can still be ingenious, patchwork and spontaneous. The characters in Han bamboo slips include seal script, official script, truth, line and grass (Cao Zhang). Han bamboo slips are not bound by the concept of writing, so they show rich creativity and eventually become a transitional writing-Han bamboo slips. There are a lot of ink marks in Juyan Han bamboo slips and Wuwei Han medical bamboo slips, which can be compared with Dunhuang Han paper ink. Close to regular script, running script and other books. The calligraphy art seen in bamboo slips is the first-hand material to study calligraphy in Qin and Han Dynasties.