diff --git a/freqtrade/optimize/optimize_reports.py b/freqtrade/optimize/optimize_reports.py
index 170e19ecc..2be3c3e62 100644
--- a/freqtrade/optimize/optimize_reports.py
+++ b/freqtrade/optimize/optimize_reports.py
@@ -313,9 +313,9 @@ def generate_strategy_stats(btdata: Dict[str, DataFrame],
         'profit_median': results['profit_ratio'].median() if len(results) > 0 else 0,
         'profit_total': results['profit_abs'].sum() / starting_balance,
         'profit_total_abs': results['profit_abs'].sum(),
-        'backtest_start': min_date,
+        'backtest_start': min_date.strftime(DATETIME_PRINT_FORMAT),
         'backtest_start_ts': int(min_date.timestamp() * 1000),
-        'backtest_end': max_date,
+        'backtest_end': max_date.strftime(DATETIME_PRINT_FORMAT),
         'backtest_end_ts': int(max_date.timestamp() * 1000),
         'backtest_days': backtest_days,
 
@@ -362,9 +362,9 @@ def generate_strategy_stats(btdata: Dict[str, DataFrame],
         strat_stats.update({
             'max_drawdown': max_drawdown,
             'max_drawdown_abs': drawdown_abs,
-            'drawdown_start': drawdown_start,
+            'drawdown_start': drawdown_start.strftime(DATETIME_PRINT_FORMAT),
             'drawdown_start_ts': drawdown_start.timestamp() * 1000,
-            'drawdown_end': drawdown_end,
+            'drawdown_end': drawdown_end.strftime(DATETIME_PRINT_FORMAT),
             'drawdown_end_ts': drawdown_end.timestamp() * 1000,
 
             'max_drawdown_low': low_val,
@@ -497,8 +497,8 @@ def text_table_add_metrics(strat_results: Dict) -> str:
         best_trade = max(strat_results['trades'], key=lambda x: x['profit_ratio'])
         worst_trade = min(strat_results['trades'], key=lambda x: x['profit_ratio'])
         metrics = [
-            ('Backtesting from', strat_results['backtest_start'].strftime(DATETIME_PRINT_FORMAT)),
-            ('Backtesting to', strat_results['backtest_end'].strftime(DATETIME_PRINT_FORMAT)),
+            ('Backtesting from', strat_results['backtest_start']),
+            ('Backtesting to', strat_results['backtest_end']),
             ('Max open trades', strat_results['max_open_trades']),
             ('', ''),  # Empty line to improve readability
             ('Total trades', strat_results['total_trades']),
@@ -546,8 +546,8 @@ def text_table_add_metrics(strat_results: Dict) -> str:
                                                strat_results['stake_currency'])),
             ('Drawdown low', round_coin_value(strat_results['max_drawdown_low'],
                                               strat_results['stake_currency'])),
-            ('Drawdown Start', strat_results['drawdown_start'].strftime(DATETIME_PRINT_FORMAT)),
-            ('Drawdown End', strat_results['drawdown_end'].strftime(DATETIME_PRINT_FORMAT)),
+            ('Drawdown Start', strat_results['drawdown_start']),
+            ('Drawdown End', strat_results['drawdown_end']),
             ('Market change', f"{round(strat_results['market_change'] * 100, 2)}%"),
         ]
 
diff --git a/tests/optimize/test_optimize_reports.py b/tests/optimize/test_optimize_reports.py
index fb4624ca3..48ba416c0 100644
--- a/tests/optimize/test_optimize_reports.py
+++ b/tests/optimize/test_optimize_reports.py
@@ -7,7 +7,7 @@ import pytest
 from arrow import Arrow
 
 from freqtrade.configuration import TimeRange
-from freqtrade.constants import LAST_BT_RESULT_FN
+from freqtrade.constants import DATETIME_PRINT_FORMAT, LAST_BT_RESULT_FN
 from freqtrade.data import history
 from freqtrade.data.btanalysis import get_latest_backtest_filename, load_backtest_data
 from freqtrade.edge import PairInfo
@@ -97,8 +97,8 @@ def test_generate_backtest_stats(default_conf, testdatadir):
     assert 'DefStrat' in stats['strategy']
     assert 'strategy_comparison' in stats
     strat_stats = stats['strategy']['DefStrat']
-    assert strat_stats['backtest_start'] == min_date.datetime
-    assert strat_stats['backtest_end'] == max_date.datetime
+    assert strat_stats['backtest_start'] == min_date.strftime(DATETIME_PRINT_FORMAT)
+    assert strat_stats['backtest_end'] == max_date.strftime(DATETIME_PRINT_FORMAT)
     assert strat_stats['total_trades'] == len(results['DefStrat']['results'])
     # Above sample had no loosing trade
     assert strat_stats['max_drawdown'] == 0.0
@@ -141,8 +141,8 @@ def test_generate_backtest_stats(default_conf, testdatadir):
     strat_stats = stats['strategy']['DefStrat']
 
     assert strat_stats['max_drawdown'] == 0.013803
-    assert strat_stats['drawdown_start'] == datetime(2017, 11, 14, 22, 10, tzinfo=timezone.utc)
-    assert strat_stats['drawdown_end'] == datetime(2017, 11, 14, 22, 43, tzinfo=timezone.utc)
+    assert strat_stats['drawdown_start'] == '2017-11-14 22:10:00'
+    assert strat_stats['drawdown_end'] == '2017-11-14 22:43:00'
     assert strat_stats['drawdown_end_ts'] == 1510699380000
     assert strat_stats['drawdown_start_ts'] == 1510697400000
     assert strat_stats['pairlist'] == ['UNITTEST/BTC']