The purpose of this study is to understand the factor that influenced the heating efficiency of the outward and inward multi-hole gas burner. The flame-hole angle and the distance from flame hole to heating object are chosen as the experimental parameter. The measurement of the flame temperature distribution is carried out on each experimental condition. LPG (Liquefied petroleum gas) is used for the test fuel gas. The compositions of LPG are propane 97.5vol%, butane 0.2vol% and methane + ethylene 2.3vol%. It is clarified that the optimum ranges of the flame-hole angle and the distance from flame hole to heating object. The experimental correlation equation is proposed for the outward and inward multi-flame-hole gas burner by design factors.