Focus of Attention and Quiet Eye (QE) of the affecting variables on aiming task performance in recent decades have always been interesting for psychologist and sport science researchers. The purpose of this study was to investigate the effectiveness of attention instructions on gaze behavior and accuracy of dart throwing of novice in low and high task load. In a semi-experimental design with repeated measurements, participant performed dart throwing under three attentional condition (internal, external and control) in two different task load (low and high). Result showed the external focus in high load task improved accuracy of dart throwing than internal focus; in the event that, for low load task there was no significant difference between the attentional conditions. Also, for QE none of attention, load task and their interaction effects was not significant. Results of research for performance supported the constrained action hypothesis; and in contrast to the conscious processing hypothesis. Also the result of gaze behavior suggests several interesting areas for future research.