Experimental investigation of the effect of blended fuel on flame spread along droplet array has been conducted. Flame spread rate is measured using high-speed chemiluminescence images of an OH radical. The flame spread is observed with the initial droplet diameter, droplet spacing, and the mixing ratio of n-heptane and n-hexadecane. The mode of flame spread is categorized into two types: a continuous mode and an intermittent one. It is seen that flame spread rate is sensitively dependent on the relative flame position to droplet spacing. For a large droplet, the flame spread time is governed by a volatile fuel (heptane), but for a small droplet, it is controlled by a less volatile fuel (hexadecane).