The objective of this article is to investigate the line-of-sight (LOS) and visual areas in order to provide a lower risk of accident and a best available view for the operator of industry machine. This paper presented a method of simulating an bulldozer operation in a virtual environment for the sake of analyzing LOS of the operator during conditions of load and unload respectively. Coverage zone tool in the JACK software was utilized to calculate the percentage of visible zones from the virtual operator’s position. At the same time, the modification of design with additional cameras was proposed based on the results of LOS analysis, which significantly improved compared with original design. The results of this study proved that the modifications (with visual monitoring system) could improve visibility of bulldozer operators to some extent according to the optimization method.