diff --git a/esphome/components/graph/graph.cpp b/esphome/components/graph/graph.cpp
index 0e437a3425..1178af911d 100644
--- a/esphome/components/graph/graph.cpp
+++ b/esphome/components/graph/graph.cpp
@@ -164,7 +164,7 @@ void Graph::draw(Display *buff, uint16_t x_offset, uint16_t y_offset, Color colo
   ESP_LOGV(TAG, "Updating graph. ymin %f, ymax %f", ymin, ymax);
   for (auto *trace : traces_) {
     Color c = trace->get_line_color();
-    uint16_t thick = trace->get_line_thickness();
+    int16_t thick = trace->get_line_thickness();
     bool continuous = trace->get_continuous();
     bool has_prev = false;
     bool prev_b = false;
@@ -178,20 +178,20 @@ void Graph::draw(Display *buff, uint16_t x_offset, uint16_t y_offset, Color colo
         if (b) {
           int16_t y = (int16_t) roundf((this->height_ - 1) * (1.0 - v)) - thick / 2 + y_offset;
           if (!continuous || !has_prev || !prev_b || (abs(y - prev_y) <= thick)) {
-            for (uint16_t t = 0; t < thick; t++) {
+            for (int16_t t = 0; t < thick; t++) {
               buff->draw_pixel_at(x, y + t, c);
             }
           } else {
             int16_t mid_y = (y + prev_y + thick) / 2;
             if (y > prev_y) {
-              for (uint16_t t = prev_y + thick; t <= mid_y; t++)
+              for (int16_t t = prev_y + thick; t <= mid_y; t++)
                 buff->draw_pixel_at(x + 1, t, c);
-              for (uint16_t t = mid_y + 1; t < y + thick; t++)
+              for (int16_t t = mid_y + 1; t < y + thick; t++)
                 buff->draw_pixel_at(x, t, c);
             } else {
-              for (uint16_t t = prev_y - 1; t >= mid_y; t--)
+              for (int16_t t = prev_y - 1; t >= mid_y; t--)
                 buff->draw_pixel_at(x + 1, t, c);
-              for (uint16_t t = mid_y - 1; t >= y; t--)
+              for (int16_t t = mid_y - 1; t >= y; t--)
                 buff->draw_pixel_at(x, t, c);
             }
           }