This study aimed to explore teachers' professional learning communities of elementary schools in Changhua County and the relationship between teaching effectiveness. Furthermore, this study also compared the different background variables of elementary school teachers in teachers' professional learning communities, teaching status on the effectiveness of the differences of perception and thus analyzed different face layers of teachers' professional learning communities of the relevant circumstances of teaching effectiveness and predictive power. This study took teachers in elementary schools in Chuanghua County as participants. Moreover, a questionnaire on the base of stratified cluster random sampling and quota sampling about the relationship between teachers' professional learning communities and teaching effectiveness was designed. Twenty percent of 484 teachers are included in 36 schools in total which contains less 12 classes, 13-24 classes, 25-48 classes and more than 49 classes. Results were collected based on 426 effective samples and 88.02% of effective sample rate. Independent sample t-test, ANOVA, Pearson product-moment correlation and regression analysis and other statistical methods are applied in this study. Results are listed as follow: 1.”Reflective dialogue” gets the highest score in teachers’ learning communities . 2.” Harmonious relationship” between the teacher and students gets the highest score in teachers’ teaching effectiveness. 3. Teachers have higher awareness in the dimensions of teachers’ learning communities and teachers’ teaching effectiveness if they are also the manager in the school. 4. Teachers have higher awareness if they served less than 5 years. 5. Teachers have higher awareness in the dimensions of teachers’ professional learning communities and teachers’ teaching effectiveness if they participated in professional learning communities. 6. Teachers’ professional learning communities and teachers’ teaching effectiveness show moderate positive correlation. 7. Teachers’ professional learning communities are predictable to the whole teaching effectiveness and “sharing value and standard” gets the highest score. According to the conclusion, this study proposes the following recommendations for consideration: 1. Suggestions for the educational executive institution: （1）Promoting teachers’ professional learning communities which allows teachers to participate in different kind of professional learning communities. （2）In order to raise whole effectiveness of school, promoting teachers’ professional learning communities and combining the evaluation of teachers’ professional development may be done. 2. Suggestions for school organization: （1）School administrators may lead colleagues to participate in professional learning communities and, thus, promote professional growth. （2）Strengthen the value of teachers’ professional learning communities and conduct a learning culture of school organization. 3. Suggestions for elementary school teachers: （1）Participate in various types of teachers’ professional learning communities and experience different positions. （2）Reflect self teaching experience through talking with the professions and conduct teachers’ professional learning communities that meet self need. （3）Harmonious relationship between the teacher and students may enhance teachers’ teaching effectiveness. 4. Suggestions for the future study: （1）Collect additional samples for cross-sample analysis and testing. （2）Field observation and qualitative study could be also made.