The relationship between handwriting and instant message (IM) frequency has not been studied in English and the reason may be related to the similar cognitive process of typing IM and handwriting words. The mental processes of producing both handwriting and typing English words are from semantics to phonology and orthography. However, the cognitive process of Chinese "Pinyin" typing used in IM activity is very different from traditional handwriting, which changes the production of handwritten glyph into the phonetic production and orthography recognition. While the IM activity itself is not conducive to literacy skill, the "Pinyin" input experience may be helpful for that. If we could separate the independent effects of IM and "Pinyin" input on handwriting, it would help us to clarify the complexity of the impact of informational and communicational technology (ICT) on literacy skills. This study investigated 449 junior school students aged 12-15 in China and found that IM directly predicts the performance of handwriting characters negatively, meanwhile, it indirectly predicts handwriting performance positively through the mediator of "Pinyin" input experience. "Pinyin" input experience compensates the negative effects of IM on handwriting. The implications of this study are that we should look at the individual effects of different types of online activity on children's literacy, and guide Chinese children to appropriately engage in useful ICT for traditional literacy development.