data test;
     input x y1 y2;
     datalines;
1 2 3
2 3 4
3 4 5
4 7 9
5 12 18
6 16 22
;

symbol1 color=red value=star  interpol=join;
symbol2 color=blue value=Circle   interpol=join ;

legend1 label=(" ") cborder=black value=("Y1" "Y2");

proc gplot data=test;
     plot y1*x y2*x/overlay legend=legend1;
run;
quit;

太感谢了,,这下ok了!