The main purpose of this study was to investigate the effects of gender difference, attituderntowards mathematics, parents' education level, and parents' locality in relation with theirrnmathematics achievement of high school students. To this end, an extensive review of thernavailable literature was made. The review was focused on four factors (i.e. gender, students'rnattitude towards mathematics, parents' educational level, and parents' locality) and mathematicsrnachievement. Based on review of related literature, basic research questions were constructedrnand framed. Three selected general secondary schools of Awi zone were used as a source of datarnfor this study. The study used mathematics achievement test and questionnaire as instruments ofrndata collection. The questionnaire and mathematics achievement test were administered 240rnstudents (120 males and 120 females) of grades nine and ten that were chosen based on simplernrandom sampling techniques. The responses of the students and the results of documentaryrndetailed examination have been analyzed and interpreted. Major statistical techniques, such as ttestrnproduct moment correlation coefficient, and multiple regressions were applied for datarnanalyses. Results of the analyses indicated that mathematics achievement was related to gender,rnmother's education level mathematics attitudefather's education level and parents' locality withrnstatistical significance. All of these five variables together explain about 47.3 percent ofrnmathematics achievement, with gender 36%, with mathematics attitude 4.3%, with mother'srneducation level 5.7%, withfather's education level 1.2%, and with parents' localityO.l% amongrngrade nine students. Further, mathematics achievement was related to gender, mathematicsrnattitude, mother's education level, father'S education level, and parents' locality with statisticalrnsignificance. All of these five variables together explain about 44.8 percent of mathematicsrnachievement, with gender 35.6%, with mathematics attitude 8.7%, with parents' Locality 0.4%rnand with mother's education level 0.1% among grade ten students