We examined whether interword spacing would facilitate acquisition of new vocabulary for second language learners of Chinese. Participants' eye movements were measured as they read new vocabulary embedded in sentences during a learning session and a test session. In the learning session, participants read sentences in traditional unspaced format and half‐read sentences with interword spacing. In the test session, all participants read unspaced sentences. Participants in the spaced learning group read the target words more quickly than those in the unspaced learning group. This benefit was maintained at test, indicating that the manipulation enhanced learning of the novel words and was not a transient effect limited to occasions when interword spacing was present in the printed text. The insertion of interword spaces may allow readers to form a more fully specified representation of the novel word, or to strengthen connections between representations of the constituent characters and the multi‐character word.