这是ggplot2做的吧，这是两个变量吗，最好把代码发上来，sec.axis参数的用法可能错了，这个参数本身需要对相应的数据进行调整。

Ori.pic<-ggplot(data=Total,aes(x=Year,y=Rate))+geom_line(aes(color=type),size=0.25)+geom_point(aes(color=type,shape=type),size=1)+theme_linedraw()+theme(axis.title=element_text(size=6),axis.text.y=element_text(size=6),axis.text.x=element_text(size=6),legend.position="top",strip.text=element_text(size=6),legend.title=element_blank(),legend.text=element_text(size=6),panel.background=element_blank())+scale_y_continuous(name="高龄比例，%",breaks=seq(10,30,5),sec.axis=sec_axis(~.*1/100,name="变化趋势",breaks=seq(0,0.3,0.06),label=format(seq(0,0.3,0.06),nsmall=1)))+scale_x_continuous(name="年份",breaks=seq(2013,2020),labels=seq(2013,2020),limits=c(2013,2020))

Ori.pic<-ggplot(data=Total,aes(x=Year,y=Rate))+geom_line(aes(color=type),size=0.25)+geom_point(aes(color=type,shape=type),size=1)+theme_linedraw()+theme(axis.title=element_text(size=6),axis.text.y=element_text(size=6),axis.text.x=element_text(size=6),legend.position="top",strip.text=element_text(size=6),legend.title=element_blank(),legend.text=element_text(size=6),panel.background=element_blank())+scale_y_continuous(name="高龄比例，%",breaks=seq(10,30,5),sec.axis=sec_axis(~.*1/100,name="变化趋势",breaks=seq(0,0.3,0.06),label=format(seq(0,0.3,0.06),nsmall=1)))+scale_x_continuous(name="年份",breaks=seq(2013,2020),labels=seq(2013,2020),limits=c(2013,2020))

谢谢，这是代码
Ori.pic<-ggplot(data=Total,aes(x=Year,y=Rate))+geom_line(aes(color=type),size=0.25)+geom_point(aes(color=type,shape=type),size=1)+theme_linedraw()+theme(axis.title=element_text(size=6),axis.text.y=element_text(size=6),axis.text.x=element_text(size=6),legend.position="top",strip.text=element_text(size=6),legend.title=element_blank(),legend.text=element_text(size=6),panel.background=element_blank())+scale_y_continuous(name="高龄比例，%",breaks=seq(10,30,5),sec.axis=sec_axis(~.*1/100,name="变化趋势",breaks=seq(0,0.3,0.06),label=format(seq(0,0.3,0.06),nsmall=1)))+scale_x_continuous(name="年份",breaks=seq(2013,2020),labels=seq(2013,2020),limits=c(2013,2020))

[img][/img]