the aim of this study is investigating the effect of teaching “metacognitive strategies” on the way which scientific information retrieval workes by the using of google scholar searching machine on the students of ms in the psycology & education faculty of allameh tabatabayi university in 2007-2008 academic year. the statistical community was the students of ms in psychology & education faculty. 36 students were selected by using the available sample method as a sample and randomly devided in two groups: experimental group (n=18) and control group (n=18). in this study the pretest - posttest control group design was used. two questionnaires of “metacognitive skills inventory for internet searching” and “scientific information retrieval” were used .the validity of them was confirmed by tenures and the researcher calculate the stability of them by using cronbach alpha coefficient. the process of performance was like this: at the first, the pretest (of “metacognitive skills inventory for internet searching” and “scientific information retrieval”) was given for both groups (experimental and control) and then, after teaching of metacognitive skills to the students of experimental group the posttest was given again from both groups. the statistical analysis was done by analaysis of covarience. findings show that the teaching of metacognitive strategies has a positive effect on the way which scientific information retrieval workes by the using of google scholar searching machine. and among the metacognitive strategies’ components there is a positive relation between regularity and scientific information retrieval.