diff --git a/packages/debug/src/browser/debug-session.tsx b/packages/debug/src/browser/debug-session.tsx
index 223f4f5b00ca1..e83fe5f55579b 100644
--- a/packages/debug/src/browser/debug-session.tsx
+++ b/packages/debug/src/browser/debug-session.tsx
@@ -374,7 +374,13 @@ export class DebugSession implements CompositeTreeElement {
     }
 
     protected async doCreateTerminal(options: TerminalWidgetOptions): Promise<TerminalWidget> {
-        let terminal = this.terminalServer.all.find(t => t.title.label === options.title || t.title.caption === options.title);
+        let terminal = undefined;
+        for (const t of this.terminalServer.all) {
+            if ((t.title.label === options.title || t.title.caption === options.title) && (await t.hasChildProcesses()) === false) {
+                terminal = t;
+            }
+        }
+
         if (!terminal) {
             terminal = await this.terminalServer.newTerminal(options);
             await terminal.start();
diff --git a/packages/terminal/src/browser/base/terminal-widget.ts b/packages/terminal/src/browser/base/terminal-widget.ts
index e63c91b851f02..8f04abf5aa0b0 100644
--- a/packages/terminal/src/browser/base/terminal-widget.ts
+++ b/packages/terminal/src/browser/base/terminal-widget.ts
@@ -47,6 +47,11 @@ export abstract class TerminalWidget extends BaseWidget {
      * Cleat terminal output.
      */
     abstract clearOutput(): void;
+
+    /**
+     * Whether the terminal process has child processes.
+     */
+    abstract hasChildProcesses(): Promise<boolean>;
 }
 
 /**
diff --git a/packages/terminal/src/browser/terminal-widget-impl.ts b/packages/terminal/src/browser/terminal-widget-impl.ts
index f04d0ac74ba4b..1fa778db17014 100644
--- a/packages/terminal/src/browser/terminal-widget-impl.ts
+++ b/packages/terminal/src/browser/terminal-widget-impl.ts
@@ -263,6 +263,10 @@ export class TerminalWidgetImpl extends TerminalWidget implements StatefulWidget
         this.term.clear();
     }
 
+    async hasChildProcesses(): Promise<boolean> {
+        return this.shellTerminalServer.hasChildProcesses(await this.processId);
+    }
+
     storeState(): object {
         this.closeOnDispose = false;
         return { terminalId: this.terminalId, titleLabel: this.title.label };
diff --git a/packages/terminal/src/common/shell-terminal-protocol.ts b/packages/terminal/src/common/shell-terminal-protocol.ts
index 8cd3b83f9547a..88b6ed128d8c3 100644
--- a/packages/terminal/src/common/shell-terminal-protocol.ts
+++ b/packages/terminal/src/common/shell-terminal-protocol.ts
@@ -20,6 +20,7 @@ import { IBaseTerminalServer, IBaseTerminalServerOptions } from './base-terminal
 export const IShellTerminalServer = Symbol('IShellTerminalServer');
 
 export interface IShellTerminalServer extends IBaseTerminalServer {
+    hasChildProcesses(processId: number | undefined): Promise<boolean>;
 }
 
 export const shellTerminalPath = '/services/shell-terminal';
diff --git a/packages/terminal/src/node/shell-terminal-server.ts b/packages/terminal/src/node/shell-terminal-server.ts
index 0c6bf8ce6af09..3b5322bc73e95 100644
--- a/packages/terminal/src/node/shell-terminal-server.ts
+++ b/packages/terminal/src/node/shell-terminal-server.ts
@@ -20,6 +20,8 @@ import { IShellTerminalServerOptions } from '../common/shell-terminal-protocol';
 import { BaseTerminalServer } from '../node/base-terminal-server';
 import { ShellProcessFactory } from '../node/shell-process';
 import { ProcessManager } from '@theia/process/lib/node';
+import { isWindows } from '@theia/core/lib/common/os';
+import * as cp from 'child_process';
 
 @injectable()
 export class ShellTerminalServer extends BaseTerminalServer {
@@ -41,4 +43,35 @@ export class ShellTerminalServer extends BaseTerminalServer {
             return Promise.resolve(-1);
         }
     }
+
+    // copied and modified from https://github.com/microsoft/vscode/blob/4636be2b71c87bfb0bfe3c94278b447a5efcc1f1/src/vs/workbench/contrib/debug/node/terminals.ts#L50-L75
+    async hasChildProcesses(processId: number | undefined): Promise<boolean> {
+        if (processId) {
+            try {
+                // if shell has at least one child process, assume that shell is busy
+                if (isWindows) {
+                    const result = cp.spawnSync('wmic', ['process', 'get', 'ParentProcessId']);
+                    if (result.stdout) {
+                        const pids = result.stdout.toString().split('\r\n');
+                        return pids.some(p => parseInt(p) === processId);
+                    }
+                } else {
+                    const result = cp.spawnSync('/usr/bin/pgrep', ['-lP', String(processId)]);
+                    if (result.stdout) {
+                        const r = result.stdout.toString().trim();
+                        if (r.length === 0 || r.indexOf(' tmux') >= 0) {
+                            return false;
+                        } else {
+                            return true;
+                        }
+                    }
+                }
+            } catch (e) {
+                // silently ignore
+            }
+        }
+        // fall back to safe side
+        return true;
+    }
+
 }