This mixed study examined the associations and effect of primary school teachers’ intrinsic and extrinsic motivation towards their performance assessed by respective head-teachers. The multi-stage random sampling involved 348 teacher-respondents and 40 head-teachers of District Hyderabad, Sindh. Both quantitative and qualitative data were collected through adapted questionnaires having 48 five-point Likert-scale items and three open-ended questions. Data were analyzed through SPSS package of 16.00 for descriptive and inferential statistical analyses at 0.05 confidence-intervals. Descriptive statistics revealed that teachers ranked their intrinsic motivation better (mean ranged1.62 to 2.18 for 11items) against extrinsic motivation (mean ranged from 2.50 to 3.97 for 14 items).Teachers’ 13 performance items did not catch supporting evidence i.e. means ranged from 1.93 to 3.97 (with 2.82 mean of means) which is disappointing one. Regarding multiple linear regression, intrinsic and extrinsic motivation significantly and moderately predicted respondents’ performance, R=.299a, r2=.290 (adjusted r2=.284), F(2, 245)=16.979, p<.001.They accounted for 29.9% variability in respondents’ performance showing better effect (unstandard beta=.306 or 30%) of extrinsic motivation t(345)=3.926, p=.000 against intrinsic one (unstandard beta=.200 or 20%)t(345)=3.926, p=.001.Regression analysis of demographical predictors reveal unsatisfactory picture despite being significant (p=.000a) with moderate level of correlation, R=.521a, r2=.272 (adjusted r2=.239), F(15, 332)=8.265, p<.001.Only two predictors i.e. xiv teaching experience and average education of family members got significant beta coefficients and p-values (p=<.05) while others (13) discarded. Difference regarding independent-samples t-test and one-way analysis of variance (ANOVA) reveal that females; widow/widower/divorced; teachers with no other source of income; and teachers with higher academic qualifications, professional qualifications, age, and monthly salary obtain statistically significant and better performance than their counterparts. Feasible suggestions collected through open-ended questions are incorporated in recommendations. Key words: intrinsic motivation, extrinsic motivation, primary school teachers’ performance,