Population management of overabundant deer is essential in many countries. Hunting is one of the ways to manage such deer so it is important to understand how hunting affects deer and numbers caught. The number caught is the product of hunter effort and hunting efficiency. However, factors affecting effort and efficiency have rarely been properly investigated. I used a Bayesian state—space model to examine the effects of landscape components and deer behavior on the effort and efficiency of two hunting methods in hunting sika deer Cervus nippon. With shooting by gun, effort increased as the deer abundance of previous year increased and the percentages of wildlife protection areas and city areas decreased. With trapping, effort increased as the percentage of wildlife protection areas decreased. Efficiency of shooting decreased as the effort of the previous year increased. With trapping, efficiency was not affected by the effort of the previous year. Efficiency of trapping plateaued with the increase of deer abundance and the decrease of efficiency in relation to deer abundance was stronger with trapping than with shooting. In conclusion, effort and efficiency were affected by landscape components, deer behavior, and hunting methods. I recommend intensive shooting in the initial phase, and after deer abundance decreases and deer vigilance increases, trapping should be adopted for a sustainable hunting efficiency.