Past researchers have examined the impact of personality types on technology usage among students from varying angles. However, due to dearth of studies on personality types and smart phone addiction among students in the Nigerian environment, this study investigated the relationship between personality types, smart phone addiction and specific phone usages among University students. A sample size of 200 was used for this study using systematic sampling technique in the selection of respondents in the study area. Findings revealed that conscientiousness and agreeableness personality types had significant positive correlation with smart phone addiction; while extraversion and neuroticism had significant negative correlation with smart phone addiction. Again personality types had significant positive and negative correlation with specific phone usages. In addition, findings revealed that majority of the specific phone usages had positive correlation with smart phone addiction. Based on the findings of this study, recommendations were made towards curbing addictive tendencies among university students in the use of smart phones.