diff --git a/libavcodec/qsvenc.c b/libavcodec/qsvenc.c
index e7e65ebfcf..50ec7065ca 100644
--- a/libavcodec/qsvenc.c
+++ b/libavcodec/qsvenc.c
@@ -514,7 +514,7 @@ static int init_video_param(AVCodecContext *avctx, QSVEncContext *q)
         }
     }
 
-    if (q->low_power) {
+    if (q->low_power == 1) {
 #if QSV_HAVE_VDENC
         q->param.mfx.LowPower = MFX_CODINGOPTION_ON;
 #else
@@ -523,7 +523,9 @@ static int init_video_param(AVCodecContext *avctx, QSVEncContext *q)
         q->low_power = 0;
         q->param.mfx.LowPower = MFX_CODINGOPTION_OFF;
 #endif
-    } else
+    } else if (q->low_power == -1)
+        q->param.mfx.LowPower = MFX_CODINGOPTION_UNKNOWN;
+    else
         q->param.mfx.LowPower = MFX_CODINGOPTION_OFF;
 
     q->param.mfx.CodecProfile       = q->profile;
diff --git a/libavcodec/qsvenc.h b/libavcodec/qsvenc.h
index ba20b6f906..31516b8e55 100644
--- a/libavcodec/qsvenc.h
+++ b/libavcodec/qsvenc.h
@@ -96,7 +96,7 @@
 { "adaptive_b",     "Adaptive B-frame placement",             OFFSET(qsv.adaptive_b),     AV_OPT_TYPE_INT, { .i64 = -1 }, -1,          1, VE },                         \
 { "b_strategy",     "Strategy to choose between I/P/B-frames", OFFSET(qsv.b_strategy),    AV_OPT_TYPE_INT, { .i64 = -1 }, -1,          1, VE },                         \
 { "forced_idr",     "Forcing I frames as IDR frames",         OFFSET(qsv.forced_idr),     AV_OPT_TYPE_BOOL,{ .i64 = 0  },  0,          1, VE },                         \
-{ "low_power", "enable low power mode(experimental: many limitations by mfx version, BRC modes, etc.)", OFFSET(qsv.low_power), AV_OPT_TYPE_BOOL, { .i64 = 0}, 0, 1, VE},\
+{ "low_power", "enable low power mode(experimental: many limitations by mfx version, BRC modes, etc.)", OFFSET(qsv.low_power), AV_OPT_TYPE_BOOL, { .i64 = -1}, -1, 1, VE},\
 
 extern const AVCodecHWConfigInternal *const ff_qsv_enc_hw_configs[];