Alcohol use, "alcohol abuse," and illicit drug use were investigated in a representative sample of 1076 urban, northern Italian high school students aged 14 to 19 years in 2001. In addition to questions on substance use, the participants were asked about school achievements and perceived substance use among friends. All the students were submitted to Zuckerman Sensation Seeking Scale (SSS) scale, Eysenck Personality Questionnaire (EPQ), Buss-Durkee Hostility Inventory (BDHI), and Parental Bonding Instrument (PBI). Lifetime alcohol use was found in 80.5%, "alcohol abuse" in 37.7%, cannabis use in 26.2%, ecstasy in 2.8%, heroin in 3.8%, and cocaine in 8.3% of the students: gender differences were significant for alcohol use, "alcohol abuse" and ecstasy use, with male subjects outnumbering females, but not for reported cannabis, heroin, and cocaine use. Early substance use onset among adolescents aged 14-16 years was detected. Higher sensation seeking on SSS, social coping impairment on EPQ, direct aggressiveness on BDHI, poor school achievements, and lower parental care on PBI were found associated with illicit drug use and "alcohol abuse" (multiple drugs users). Increased levels of aggressiveness and sensation seeking were evidenced both in minimal experimenters (ME) and habitual users (HU), without any significant difference, in comparison with abstinent students. Similarly, ME scored higher than abstinent subjects on EPQ for social coping impairment, but lower than HU. Parental care perception was lower in HU, but not in ME with, respect to abstinent subjects. Pearson inverse correlation was demonstrated between PBI scores and EPQ maladaptation and BDHI aggressiveness. Data from this preliminary pilot study suggest that temperamental traits and personality changes may be associated to early substance use "proneness" and reduced perception of parental care.