diff --git a/superset/mcp_service/chart/chart_utils.py b/superset/mcp_service/chart/chart_utils.py
index d3801e66885..8c3ba134288 100644
--- a/superset/mcp_service/chart/chart_utils.py
+++ b/superset/mcp_service/chart/chart_utils.py
@@ -290,6 +290,10 @@ def map_xy_config(config: XYChartConfig) -> Dict[str, Any]:
         "metrics": metrics,
     }
 
+    # Add time grain if specified (for temporal x-axis columns)
+    if config.time_grain:
+        form_data["time_grain_sqla"] = config.time_grain
+
     # CRITICAL FIX: For time series charts, handle groupby carefully to avoid duplicates
     # The x_axis field already tells Superset which column to use for time grouping
     groupby_columns = []
diff --git a/superset/mcp_service/chart/schemas.py b/superset/mcp_service/chart/schemas.py
index f28d7e75f69..48f3e45ba16 100644
--- a/superset/mcp_service/chart/schemas.py
+++ b/superset/mcp_service/chart/schemas.py
@@ -36,6 +36,7 @@ from pydantic import (
     PositiveInt,
 )
 
+from superset.constants import TimeGrain
 from superset.daos.base import ColumnOperator, ColumnOperatorEnum
 from superset.mcp_service.common.cache_schemas import (
     CacheStatus,
@@ -678,6 +679,15 @@ class XYChartConfig(BaseModel):
     kind: Literal["line", "bar", "area", "scatter"] = Field(
         "line", description="Chart visualization type"
     )
+    time_grain: TimeGrain | None = Field(
+        None,
+        description=(
+            "Time granularity for the x-axis when it's a temporal column. "
+            "Common values: PT1S (second), PT1M (minute), PT1H (hour), "
+            "P1D (day), P1W (week), P1M (month), P3M (quarter), P1Y (year). "
+            "If not specified, Superset will use its default behavior."
+        ),
+    )
     group_by: ColumnRef | None = Field(None, description="Column to group by")
     x_axis: AxisConfig | None = Field(None, description="X-axis configuration")
     y_axis: AxisConfig | None = Field(None, description="Y-axis configuration")
diff --git a/tests/unit_tests/mcp_service/chart/test_chart_utils.py b/tests/unit_tests/mcp_service/chart/test_chart_utils.py
index 4f4f3a3857b..f2e9d966c89 100644
--- a/tests/unit_tests/mcp_service/chart/test_chart_utils.py
+++ b/tests/unit_tests/mcp_service/chart/test_chart_utils.py
@@ -275,6 +275,82 @@ class TestMapXYConfig:
         assert result["show_legend"] is False
         assert result["legend_orientation"] == "top"
 
+    def test_map_xy_config_with_time_grain_month(self) -> None:
+        """Test XY config mapping with monthly time grain"""
+        config = XYChartConfig(
+            chart_type="xy",
+            x=ColumnRef(name="order_date"),
+            y=[ColumnRef(name="revenue", aggregate="SUM")],
+            kind="bar",
+            time_grain="P1M",
+        )
+
+        result = map_xy_config(config)
+
+        assert result["viz_type"] == "echarts_timeseries_bar"
+        assert result["x_axis"] == "order_date"
+        assert result["time_grain_sqla"] == "P1M"
+
+    def test_map_xy_config_with_time_grain_day(self) -> None:
+        """Test XY config mapping with daily time grain"""
+        config = XYChartConfig(
+            chart_type="xy",
+            x=ColumnRef(name="created_at"),
+            y=[ColumnRef(name="count", aggregate="COUNT")],
+            kind="line",
+            time_grain="P1D",
+        )
+
+        result = map_xy_config(config)
+
+        assert result["viz_type"] == "echarts_timeseries_line"
+        assert result["x_axis"] == "created_at"
+        assert result["time_grain_sqla"] == "P1D"
+
+    def test_map_xy_config_with_time_grain_hour(self) -> None:
+        """Test XY config mapping with hourly time grain"""
+        config = XYChartConfig(
+            chart_type="xy",
+            x=ColumnRef(name="timestamp"),
+            y=[ColumnRef(name="requests", aggregate="SUM")],
+            kind="area",
+            time_grain="PT1H",
+        )
+
+        result = map_xy_config(config)
+
+        assert result["time_grain_sqla"] == "PT1H"
+
+    def test_map_xy_config_without_time_grain(self) -> None:
+        """Test XY config mapping without time grain (should not set time_grain_sqla)"""
+        config = XYChartConfig(
+            chart_type="xy",
+            x=ColumnRef(name="date"),
+            y=[ColumnRef(name="revenue")],
+            kind="line",
+        )
+
+        result = map_xy_config(config)
+
+        assert "time_grain_sqla" not in result
+
+    def test_map_xy_config_with_time_grain_and_groupby(self) -> None:
+        """Test XY config mapping with time grain and group by"""
+        config = XYChartConfig(
+            chart_type="xy",
+            x=ColumnRef(name="order_date"),
+            y=[ColumnRef(name="revenue", aggregate="SUM")],
+            kind="line",
+            time_grain="P1W",
+            group_by=ColumnRef(name="category"),
+        )
+
+        result = map_xy_config(config)
+
+        assert result["time_grain_sqla"] == "P1W"
+        assert result["groupby"] == ["category"]
+        assert result["x_axis"] == "order_date"
+
 
 class TestMapConfigToFormData:
     """Test map_config_to_form_data function"""