Fire design is the basis of quantitative evaluation in performance-based fire design, which includes the determination of fire location and heat release rate (HRR). Take large-scale exhibition hall for example, utilizing fire radiation model and smoke radiation model and combining the simulate result of CFAST 6.0, analysis of fire grown situation is taken with different fire locations in large space. Research reveals: only considering fire radiation, when fire develops in a location of bilateral symmetry, fire grows faster with HRR peak values are larger and the time of attain HRR peak value earlier and duration time are shorter than others. Thereinto, fire grow fastest when fire develops in the location of center symmetry. Moreover, combining fire radiation and smoke radiation, HRR peak values consumedly increases and almost the same in each scenarios. But other rules, which contain fire growth and the correlative time, when considering fire radiation and smoke radiation, is the same as the situation of just considering fire radiation.