diff --git a/doc/users/next_whats_new/multiple_labels_for_Axes_plot.rst b/doc/users/next_whats_new/multiple_labels_for_Axes_plot.rst
new file mode 100644
index 000000000000..1584357dc618
--- /dev/null
+++ b/doc/users/next_whats_new/multiple_labels_for_Axes_plot.rst
@@ -0,0 +1,19 @@
+An iterable object with labels can be passed to `.Axes.plot`
+------------------------------------------------------------
+
+When plotting multiple datasets by passing 2D data as *y* value to
+`~.Axes.plot`, labels for the datasets can be passed as a list, the
+length matching the number of columns in *y*.
+
+.. plot::
+
+ import matplotlib.pyplot as plt
+
+ x = [1, 2, 3]
+
+ y = [[1, 2],
+ [2, 5],
+ [4, 9]]
+
+ plt.plot(x, y, label=['low', 'high'])
+ plt.legend()
diff --git a/lib/matplotlib/axes/_axes.py b/lib/matplotlib/axes/_axes.py
index 9e6bee8a18a8..ead143489a3b 100644
--- a/lib/matplotlib/axes/_axes.py
+++ b/lib/matplotlib/axes/_axes.py
@@ -1499,6 +1499,8 @@ def plot(self, *args, scalex=True, scaley=True, data=None, **kwargs):
If you make multiple lines with one plot call, the kwargs
apply to all those lines.
+ In case if label object is iterable, each its element is
+ used as label for a separate line.
Here is a list of available `.Line2D` properties:
diff --git a/lib/matplotlib/axes/_base.py b/lib/matplotlib/axes/_base.py
index c6309b5ab9df..6692982ce0aa 100644
--- a/lib/matplotlib/axes/_base.py
+++ b/lib/matplotlib/axes/_base.py
@@ -293,6 +293,12 @@ def __call__(self, *args, data=None, **kwargs):
replaced[label_namer_idx], args[label_namer_idx])
args = replaced
+ if len(args) >= 4 and not cbook.is_scalar_or_string(
+ kwargs.get("label")):
+ raise ValueError("plot() with multiple groups of data (i.e., "
+ "pairs of x and y) does not support multiple "
+ "labels")
+
# Repeatedly grab (x, y) or (x, y, format) from the front of args and
# massage them into arguments to plot() or fill().
@@ -446,8 +452,22 @@ def _plot_args(self, tup, kwargs, return_kwargs=False):
ncx, ncy = x.shape[1], y.shape[1]
if ncx > 1 and ncy > 1 and ncx != ncy:
raise ValueError(f"x has {ncx} columns but y has {ncy} columns")
- result = (func(x[:, j % ncx], y[:, j % ncy], kw, kwargs)
- for j in range(max(ncx, ncy)))
+
+ label = kwargs.get('label')
+ n_datasets = max(ncx, ncy)
+ if n_datasets > 1 and not cbook.is_scalar_or_string(label):
+ if len(label) != n_datasets:
+ raise ValueError(f"label must be scalar or have the same "
+ f"length as the input data, but found "
+ f"{len(label)} for {n_datasets} datasets.")
+ labels = label
+ else:
+ labels = [label] * n_datasets
+
+ result = (func(x[:, j % ncx], y[:, j % ncy], kw,
+ {**kwargs, 'label': label})
+ for j, label in enumerate(labels))
+
if return_kwargs:
return list(result)
else:
diff --git a/lib/matplotlib/tests/test_legend.py b/lib/matplotlib/tests/test_legend.py
index cd0cd8be85ca..cebf26ea066e 100644
--- a/lib/matplotlib/tests/test_legend.py
+++ b/lib/matplotlib/tests/test_legend.py
@@ -671,3 +671,65 @@ def test_no_warn_big_data_when_loc_specified():
ax.plot(np.arange(5000), label=idx)
legend = ax.legend('best')
fig.draw_artist(legend) # Check that no warning is emitted.
+
+
+@pytest.mark.parametrize('label_array', [['low', 'high'],
+ ('low', 'high'),
+ np.array(['low', 'high'])])
+def test_plot_multiple_input_multiple_label(label_array):
+ # test ax.plot() with multidimensional input
+ # and multiple labels
+ x = [1, 2, 3]
+ y = [[1, 2],
+ [2, 5],
+ [4, 9]]
+
+ fig, ax = plt.subplots()
+ ax.plot(x, y, label=label_array)
+ leg = ax.legend()
+ legend_texts = [entry.get_text() for entry in leg.get_texts()]
+ assert legend_texts == ['low', 'high']
+
+
+@pytest.mark.parametrize('label', ['one', 1, int])
+def test_plot_multiple_input_single_label(label):
+ # test ax.plot() with multidimensional input
+ # and single label
+ x = [1, 2, 3]
+ y = [[1, 2],
+ [2, 5],
+ [4, 9]]
+
+ fig, ax = plt.subplots()
+ ax.plot(x, y, label=label)
+ leg = ax.legend()
+ legend_texts = [entry.get_text() for entry in leg.get_texts()]
+ assert legend_texts == [str(label)] * 2
+
+
+@pytest.mark.parametrize('label_array', [['low', 'high'],
+ ('low', 'high'),
+ np.array(['low', 'high'])])
+def test_plot_single_input_multiple_label(label_array):
+ # test ax.plot() with 1D array like input
+ # and iterable label
+ x = [1, 2, 3]
+ y = [2, 5, 6]
+ fig, ax = plt.subplots()
+ ax.plot(x, y, label=label_array)
+ leg = ax.legend()
+ assert len(leg.get_texts()) == 1
+ assert leg.get_texts()[0].get_text() == str(label_array)
+
+
+def test_plot_multiple_label_incorrect_length_exception():
+ # check that excepton is raised if multiple labels
+ # are given, but number of on labels != number of lines
+ with pytest.raises(ValueError):
+ x = [1, 2, 3]
+ y = [[1, 2],
+ [2, 5],
+ [4, 9]]
+ label = ['high', 'low', 'medium']
+ fig, ax = plt.subplots()
+ ax.plot(x, y, label=label)
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