从您的评论中注意到，预先设置数据集的子集不是您的选择，因此这里有一个后期制作方法：

# create plot
p <- ggplot(data=df,aes(x=x,y=y))+
  geom_point()+
  facet_grid2(row~col, scales = "free", independent = "all")

# convert to grob
gp <- ggplotGrob(p)

# check which are the columns of the gtable to strip out
# (for the example, we want to strip out content from cols 4-5)
gp                             # examine layout in console
gtable::gtable_show_layout(gp) # examine layout in viewer

# strip them out
gp <- gp %>%
  cowplot::gtable_remove_grobs(names = gp$layout %>% 
                                 filter(r %in% 4:5) %>% 
                                 pull(name)) %>%
  cowplot::gtable_squash_cols(cols = 4:5)

# plot the result
plot(gp)

数据：

set.seed(123)
df <- data.frame(x=rnorm(80),y=rnorm(80),
                 col=rep(c(" ", "B","C"," ","B","C","B","C"),each=10),
                 row=rep(c("a","a","a","b","b","b","c","c"),each=10))

一种方法是使用subset()：

library(ggplot2)
library(ggh4x)

df %>%
  subset(!(row == "a" & col == " ")) %>%
  ggplot(aes(x=x,y=y)) +
  geom_point() +
  facet_grid2(row~col, scales = "free", independent = "all")