diff --git a/finrl/env/env_stocktrading.py b/finrl/env/env_stocktrading.py
index ccb615eaa..ced683f79 100644
--- a/finrl/env/env_stocktrading.py
+++ b/finrl/env/env_stocktrading.py
@@ -132,7 +132,7 @@ def _buy_stock(self, index, action):
         def _do_buy():
             if self.state[index+1]>0: 
                 #Buy only if the price is > 0 (no missing data in this particular date)       
-                available_amount = self.state[0] // self.state[index+1]
+                available_amount = self.state[0] // ((self.state[index+1])*(1+ self.buy_cost_pct))
                 # print('available_amount:{}'.format(available_amount))
                 
                 #update balance
@@ -377,4 +377,4 @@ def _seed(self, seed=None):
     def get_sb_env(self):
         e = DummyVecEnv([lambda: self])
         obs = e.reset()
-        return e, obs
\ No newline at end of file
+        return e, obs