Street vendors use sidewalks to display goods and services. The reduction of sidewalk space by sidewalk vending activity forces pedestrians to take evasive action by changing walking speed and/or direction. Based on previous qualitative studies pedestrian evasive movements are related to pedestrian level of service and sharing carriageways. The aim of this paper was to investigate the effect of typical sidewalk vendor on average pedestrian walking speed and lateral position. The study used a field observation followed by a controlled walking experiment to study pedestrian behavior in the presence of typical sidewalk vendor. A univariate analysis of variance (ANOVA) of pedestrian trajectories, extracted from a walking experiment, showed that the average pedestrian lateral position and walking speed were significantly affected by the presence of a sidewalk vendor, pedestrian flow rate and the interaction effect of the two (p<0.05). The effect size also varied with the width of a vending stall and vendor's location relative to the pedestrian's desired trajectory. The results are consistent with previous observations and findings about pedestrian sidewalk behavior in the presence of sidewalk vendor. The findings may contribute in designing and or monitoring sidewalk vending activities.