Yes, you can apply for a visa to China in Japan if your Alien Card is valid for more than 6 months when you submit your visa application. Please pay attention to the consular district of Chinese emhbassy and each consulate, you need to submit to the one which holds the consular jurisdiction of the place you reside. They may not have mail service for that. The requirements are as follows: A valid passport with enough blank pages; Certificate of alien registration; One recently taken, bareheaded, full-faced photo and a Chinese hotel reservation certificate and a two-way air ticket.