Objective　To explore the form and effect of an after-class autonomic model aiming at improving English writing competence. Methods　Objects were chosen through pre-experimental test and were divided into three groups: control class（n=44）， experimental class one （n=47） and ex-perimental class two（n=48）. Objects from the control class did not keep journals while those from the two experimental classes kept journals for twelve weeks. Teacher comments， student's mutual com-ments and exhibitions of excellent journals were conducted in experimental class one. All the objects took a post-experimental test at the end of the experiment and a survey was conducted among the ob-jects from the two experimental classes. SPSS16.0 was used for data-processing. T-tests were adopted to compare the pre-experimental and the post-experimental test scores of all classes（P<0.05 indicates significant difference）. Variance analyses were conducted to compare the post-experimental tests （P<0.05 indicates significant difference）. Results　The T-test results of the control class， experimental class one and experimental class two were respectively as follows： t=1.59，P=0.12； t=13.42，P =0.00；t=11.68，P=0.00. The results of the variance analyses were： F=48.87， P=0.00. The T-value of the SNK comparison between experimental class one and the control class was 9.12（P=0.00）， that between ex-perimental class two and the control class was 7.99（P=0.00） while that between experimental class one and experimental class two was 1.19（P=0.23）. Results of the survey: 98.94% of the objects agreed that keeping English journals could help to improve the fluency and accuracy of English writing； 85.11% regarded keeping English journals as an effective way to improve English writing competence； 80.85% believed than keeping English journals could help to put the newly-learnt vocabulary to use. 50% of the objects deemed that keeping English journals could improve writing interest and 69.15% thought that it could enhance writing confidence. 70.21% believed that exhibiting excellent journals could create good writing atmosphere and inspire writing motivation. Conclusions　Keeping English journals could improve English writing competence significantly through after-class autonomic writing， and it can improve writing interest and confidence. However， the impacts of teacher comments， stu-dent's mutual comments and the exhibition of excellent journals on writing competence are not signifi-cant.