I would like to make a new data frame which only includes common rows of two separate data.frame. example:

data.frame 1

1 id300
2 id2345
3 id5456
4 id33
5 id45
6 id54

data.frame2

1 id832
2 id300
3 id1000
4 id45
5 id984
6 id5456
7 id888

　So I want my output be:

1 id300
2 id45
3 id5456

any suggestion please?

The appropriate dplyr function here is inner_join (returns all rows from df x that have a match in df y.)

library(dplyr)
inner_join(df1, df2)

      V1
1  id300
2 id5456
3   id45

Note: the rows are returned in the order in which they are in df1. If you did inner_join(df2, df1), id45 would come before id5456.