Older adults are considered as being among the most vulnerable age group who are inclined to road crashes injuries, and the rate of fatality between the aged drivers, pedestrians, and pedal cyclists have been continuously on the rise at an alarming rate. Because of the statewide growth in motor vehicle crashes involving the older people, the Illinois Department of Transportation (IDOT) has recognized older drivers as a prominence area in the Illinois Strategic Highway Plan. The main objective of this study is to identify roadway geometric, operational, environmental, and socioeconomic variables significantly associated with senior people crashes. First, preliminary analysis of the six years of crash data from 2011 to 2016 of the state of Illinois was performed and different characteristics of crash injury for older people (age 65 and above) was determined and compared with those of other age groups. After that, Multiple Logistic Regression Model has been employed to model the correlation between older people severe crashes and crash characteristics and socioeconomic characteristics. The results have revealed that "median household income", "uninsured adult percentage", "African American percentage" and the average number of people served by a single physician in a particular county are the socioeconomic factors for severe crashes among older people. In addition to the socioeconomic parameters, crash level parameters including weather condition, road surface condition, light, roadway alignment, types of vehicles, vehicle defects, temporal, gender, traffic control systems etc. are significant crash level predictors for severe older people crashes in Illinois.