To determine the associations between autism developmental profiles and cooperation with an oral health screening among preschool children with autism spectrum disorders (ASDs). A random sample of Special Child Care Centres registered with the Government Social Welfare Department in Hong Kong was selected (19 out of 37 Centres). All preschool children with ASDs were invited to participate in the oral health survey and 347 children agreed to participate (among 515 invited). A checklist of autism developmental profiles: (1) level of cognitive functioning, (2) social skills development, (3) communication skills development, (4) reading skills and (5) challenging behaviours was ascertained. Feasibility of conducting oral health screening in preschool children with ASDs was associated with their cognitive functioning (p = 0.001), social skills development (p = 0.002), communication skills development (p 0.001), reading skills (p 0.001) and challenging behaviours (p = 0.06). In regression analyses accounting for age (in months) and gender, inability to cooperate with an oral health screening was associated with high level of challenging behaviours (OR 10.50, 95 % CI 2.89-38.08, p 0.001) and reduced cognitive functioning (OR 5.29, 95 % CI 1.14-24.61, p = 0.034). Age (in months) was positively associated with likelihood of cooperative behaviour with an oral health screening (OR 1.06, 95 % CI 1.03, 1.08, p 0.001). Feasibility of conducting population-wide oral health screening among preschool children with ASDs is associated with their developmental profiles; and in particular levels of cognitive functioning, and challenging behaviours. (author abstract)