The objective of the study is to determine the effect of parent's socio economic background on Mathematics anxiety and academic achievement in high school students. The sample comprised 540 (268 boys and 272 girls) 8th, 9th and 10th grade high school students from Karnataka, Kerala and Tamil Nadu states. The answers of students were evaluated using a Mathematics anxiety scale (MAS) and parent's socio economic background estimated by a socio economic background questionnaire. The results have revealed that among the parent's socio economic background variables, only parent's education has a negative correlation with Mathematics anxiety and multivariate regression for this model revealed that combination of age, income and education can be a good predictor for Mathematics anxiety. The second part of results also exposed that parent's income and parent's education has a significant positive correlation with mathematics anxiety and multivariate regression for this model also revealed that combination of parent's socio economic background can be a good predictor for Mathematics anxiety. On the basis of these findings, it was recommended that special classes should be provided for training of parents and they should be prepared in counseling and pedagogical classes.