eng Science and Education Publishing Turkish Journal of Analysis and Number Theory 2333-1232 2016-08-27 4 3 82 86 10.12691/tjant-4-3-5 TJANT2016435 article M. A. Bakhit mabakhit@jazanu.edu.sa 1 Department of Mathematics, Faculty of Science, Jazan University, Jazan, Saudi Arabia In this paper, we define the classes QK of quaternion-valued functions, then we characterize quaternion Bloch functions by quaternion QK functions in the unit ball of , Further, some important basic properties of these functions are also considered. http://pubs.sciepub.com/tjant/4/3/5/tjant-4-3-5.pdf Clifford analysis quaternion Bloch space Q_K spaces