Methylation of histone by protein arginine methyltransferases (PRMTs) plays an important role in gene regulation. PRMT1- and PRMT4-catalyzed methyl-arginine is involved in transcription activation, while PRMT5- and PRMT6-catalyzed methyl-arginine is associated with transcription repression. Histone arginine methylation can be dynamically regulated in vivo, and methyl-arginine is demethylated by “arginine demethylase”. Here, the most recent progresses in the methylation studies of histone arginine were summarized.