Semantic priming is the effect that the activation of meaning can spread to the neighboring nodes. A large number of studies have confirmed the effect within certain language (e.g., Hernandez et al. 1996；Heyman et al. 2016；Kootstra & Muysken 2017) and across different languages (e.g., Ferré et al. 2015). Recent research has extended semantic priming effect to the cross-modal level. Results from those studies indicate meaning can spread between language and gesture system (e.g., Kelly et al. 2004; Yap et al. 2011), which is attributed to the iconic feature of gesture. Sign language, as a natural language, bears both iconicity and symbolicity. However, few studies examined the semantic priming effect between spoken language and sign language. In addition, some researchers started to pay attention to the modulating role of L2 proficiency in semantic priming (e.g., Nakayama et al. 2016). Therefore, the current study investigated semantic priming effect in Chinese monolinguals and Chinese-Chinese sign language (CSL) bilinguals. In the experiment, a word judgment task was used to investigate the semantic priming effect between Chinese and CSL. Participants were asked to watch a video clip of a hand gesture of a CSL sign, and then judge if a target word is a real Chinese word or a fake one. Due to the material type that half of the CSL signs are iconic and half of the real words are semantically related to CSL signs, if there exists cross-modal semantic priming effect participants’ judging behavior would be different according to different characteristics of signs and words. Thus, a measure of cross-modal semantic priming effect can be computed by comparing the mean judgment RT for the real Chinese words semantically related or irrelated to CSL signs. Experiment results showed that in the trials of iconic signs, both L2 CSL signers and Chinese monolinguals judged semantically related words more efficiently than semantically irrelated words. However, in trails of symbolic signs, only L2 CSL signers judged semantically related words more efficiently than irrelated words. Chinese monolinguals judged the two types of words with no significant difference. The results indicate that there exists cross-modal semantic priming effect, but the effect is modulated by sign iconicity and L2 CSL proficiency. Chinese-CSL bilinguals may have constructed a Chinese lexicon system and a CSL lexicon system, but they share one conceptual system. Therefore, the meaning activation can spread across modal from CSL signs to Chinese words. However, Chinese monolinguals do not have CSL lexicon system. The cross-modal semantic priming effect of Chinese monolinguals relies on the visual similarity of iconic signs. Together, the results attribute the cross-modal semantic priming effect to the shared conceptual representation of Chinese and CSL. Iconic signs, like iconic gestures, can activate meaning for non-signers, but symbolic signs cannot.