Hey there! I’ve tackled this exact issue before with python-pptx, so let me walk you through how to do both horizontal and vertical cell merges clearly. The library doesn’t have a single "merge cells" function out of the box, but you can achieve it using built-in properties for grid spanning and vertical merging.

Let’s start with a complete example that covers both merge types, then break down each part.

First, Set Up Your Basic Table #

First, we’ll create a presentation, add a slide, and insert a table to work with:

from pptx import Presentation
from pptx.util import Inches
from pptx.enum.table import Merge

# Create a new presentation and blank slide
prs = Presentation()
slide = prs.slides.add_slide(prs.slide_layouts[5])  # Blank slide layout

# Add a 5-row, 4-column table
left, top = Inches(1), Inches(1)
width, height = Inches(6), Inches(4)
table = slide.shapes.add_table(5, 4, left, top, width, height).table

# Populate initial cell content (for reference)
for row_idx in range(5):
    for col_idx in range(4):
        table.cell(row_idx, col_idx).text = f"Row {row_idx+1}, Col {col_idx+1}"

Horizontal Merge (Span Multiple Columns) #

To merge cells horizontally, you’ll use the grid_span property of the starting cell. This tells PowerPoint how many columns the cell should occupy.

Example: Merge Row 1, Columns 1-3 #

# Target the starting cell (Row 1, Column 1 = index 0,0)
start_cell = table.cell(0, 0)
start_cell.text = "Horizontal Merge (3 Columns)"

# Set grid_span to 3 to span 3 columns
start_cell.grid_span = 3

# Clear content from the cells being merged into (optional but clean)
for col_idx in range(1, 3):
    table.cell(0, col_idx).text = ""

Vertical Merge (Span Multiple Rows) #

Vertical merging uses the v_merge enum to mark a starting cell and subsequent cells that should be merged into it.

Example: Merge Column 1, Rows 2-4 #

# Target the starting cell (Row 2, Column 1 = index 1,0)
vertical_start = table.cell(1, 0)
vertical_start.text = "Vertical Merge (3 Rows)"
# Mark this as the first cell in the merged group
vertical_start.v_merge = Merge.FIRST

# Mark subsequent cells as part of the merge and clear their content
for row_idx in range(2, 4):
    merged_cell = table.cell(row_idx, 0)
    merged_cell.v_merge = Merge.CONTINUE
    merged_cell.text = ""

Final Touches & Save #

Adjust row heights/column widths if needed to make merged cells look clean, then save your presentation:

# Adjust row height for the horizontal merged row
table.rows[0].height = Inches(0.8)
# Adjust column width for the vertical merged column
table.columns[0].width = Inches(1.5)

# Save the presentation
prs.save("merged_table_example.pptx")

Key Notes #

• Only the starting cell’s content will be visible in the merged area, so always clear content from cells being merged into.
• For horizontal merges, grid_span must match the number of columns you want to span (e.g., 2 for merging two columns).
• For vertical merges, make sure every cell in the merged range has either Merge.FIRST (only one) or Merge.CONTINUE (all others).

Hope this solves your problem! If you run into edge cases (like merging irregular ranges), feel free to follow up with details.

内容的提问来源于stack exchange，提问作者EugenS