Sleep is important for cognitive restoration and quality of life in students. There are few studies about sleep quality (SQ) and effects of diurnal and nocturnal schedules upon students in Columbia. Objective: To assess and correlate SQ, sleepiness, and attention. Participants: 69 men and 88 women (mean age = 22.7 years, SD = 4.11), students of business administration. Instruments: Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, and Toulouse-Piéron’s Attention Test. Results: 51% of the students did not have an optimal SQ, but this was not significantly different between diurnal and nocturnal schedules. Seventy-six percent of students showed some level of sleepiness and 59% of them with a moderate or marked level of sleepiness. Students on nocturnal schedules tended to be sleepier and have a worse SQ than those on diurnal schedules. Sleep latency showed a positive correlation with attention (Spearman’s rho = 0. 227, p = 0.004). It is recommended that future studies measure a wider range of variables to enable the issue of how broad are the effects of diurnal vs. nocturnal schedules to be focused upon more clearly.