diff --git a/example/ck_tile/18_hstu_attention/README.md b/example/ck_tile/18_hstu_attention/README.md
index bade486980..6e1f978657 100644
--- a/example/ck_tile/18_hstu_attention/README.md
+++ b/example/ck_tile/18_hstu_attention/README.md
@@ -54,6 +54,7 @@
         .insert("minfull_len", "6", "sequence length at the end of the query sequence that should be included for attention")
         .insert("init_qkv", "0", "initialize q, k, v tensor from local files q.dat, k.dat and v.data")
         .insert("seed", "13579", "seed by the uniform or normal distribution generator")
+        .insert("alpha", "0", "scale factor of P=Q@K. 0 means equal to 1/sqrt(hdim)")
         .insert("save_mask", "1", "save the mask tensor to disk by the CPU validation codes")
         .insert("perf", "0", "weather measure execution time or not");
         .insert("dump_output", "0", "dump both device and reference hstu attention outputs to files, only used when validation is true");
diff --git a/example/ck_tile/18_hstu_attention/example_hstu_attention.cpp b/example/ck_tile/18_hstu_attention/example_hstu_attention.cpp
index 48fcba02ff..69e9530bc8 100644
--- a/example/ck_tile/18_hstu_attention/example_hstu_attention.cpp
+++ b/example/ck_tile/18_hstu_attention/example_hstu_attention.cpp
@@ -108,6 +108,7 @@ auto create_args(int argc, char* argv[])
         .insert("context_len", "6", "sequence length at the begin of the query sequence the should be included for attention")
         .insert("minfull_len", "6", "sequence length at the end of the query sequence that should be included for attention")
 	.insert("seed", "13579", "seed by the uniform or normal distribution generator")
+        .insert("alpha", "0", "scale factor of P=Q@K. 0 means equal to 1/sqrt(hdim)")
         .insert("init_qkv", "0", "initialize q, k, v tensor from local files q.dat, k.dat and v.data")
         .insert("save_mask", "0", "save the mask tensor to disk by the CPU validation codes")
         .insert("perf", "0", "weather measure execution time or not")
@@ -221,6 +222,7 @@ bool run(const ck_tile::ArgParser& arg_parser)
     int contextual_seqlen    = arg_parser.get_int("context_len");
     int min_full_attn_seqlen = arg_parser.get_int("minfull_len");
 
+    float alpha       = arg_parser.get_float("alpha");
     int seed          = arg_parser.get_int("seed");
     bool measure_perf = static_cast<bool>(arg_parser.get_int("perf"));
     bool dump_output  = static_cast<bool>(arg_parser.get_int("dump_output"));
@@ -391,7 +393,7 @@ bool run(const ck_tile::ArgParser& arg_parser)
 
     HstuAttentionFwdParams params;
 
-    float scale_s = 1.0f / std::sqrt(hdim_qk);
+    float scale_s = (alpha != 0.f) ? alpha : 1.0f / std::sqrt(hdim_qk);
 
     if(is_jagged)
     {