The purpose for this study was to assess knowledge and attitude of sexual risk behaviour among senior secondary school students in Bauchi State, Nigeria. An expost facto research design was used. A total of 76,279 constituted the number of respondents used for this study. A multi stage sampling procedurewhich included stratified and proportionate sampling procedures were used to draw the sample size from the senior secondary schools within the three (3) senatorial zones of the state, which are Bauchi north, Bauchi central and Bauchi south. The instrument used was a close- ended questionnaire. Three hundred and seventy eight(378) copies of the questionnaire wereadministered using simple random sample technique to the respondent. The data collected were analyzed using simple frequency and percentages to describe the demograhphic characteristics of the respondents, descriptive statistics of mean and standard deviation were used to answer the research questions.One sample t-test, independent sample t-test and ANOVA were used to testthe formulated hypotheses. The finding of the study revealed that knowledge of sexual risk behaviour among senior secondary school students in Bauchi State is significant (t = 4.120; p = 0.021), attitude towards sexual risk behaviour among senior secondary school students in Bauchi State is not significant (t = 1.341; p=0.81), demographic characteristics of the respondents such as age and gender do not significantly influence the knowledge and attitude towards sexual risk behaviour among senior secondary school studnets in Bacuhi State.On the basis of the conclusion drawn thatsenior secondary school students in Bauchi state have significant knowledge of sexual risk behaviour and that attitude towards sexual risk behavviiours among senior secondary school students in Bauchi State is negative. It was recommended among others that continuous education through organizing of seminars and workshops by the school management should be made to sustain and promote the knowledge the students have acquired. Enlightenment campaign should be embarked upon by both government and school authority for students to enable them overcome their negative attitude towards sexual risk behaviour.