diff --git a/Cargo.lock b/Cargo.lock
index 03eb317111b4..01a3601b7e14 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -7169,6 +7169,7 @@ version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1e9cd434a998747dd2c4276bc96ee2e0c7a2eadf3cae88e52be55a05fa9053f5"
 dependencies = [
+ "base64 0.21.7",
  "bitflags 2.9.0",
  "bytes",
  "futures-util",
diff --git a/crates/goose-cli/Cargo.toml b/crates/goose-cli/Cargo.toml
index fb16ced65e80..b4e3d3da4c1a 100644
--- a/crates/goose-cli/Cargo.toml
+++ b/crates/goose-cli/Cargo.toml
@@ -52,7 +52,7 @@ nix = { version = "0.30.1", features = ["process", "signal"] }
 tar = "0.4"
 # Web server dependencies
 axum = { version = "0.8.1", features = ["ws", "macros"] }
-tower-http = { version = "0.5", features = ["cors", "fs"] }
+tower-http = { version = "0.5", features = ["cors", "fs", "auth"] }
 http = "1.0"
 webbrowser = "1.0"
 indicatif = "0.17.11"
diff --git a/crates/goose-cli/src/cli.rs b/crates/goose-cli/src/cli.rs
index a760a8b98fd1..4600e5a11bb0 100644
--- a/crates/goose-cli/src/cli.rs
+++ b/crates/goose-cli/src/cli.rs
@@ -703,6 +703,10 @@ enum Command {
         /// Open browser automatically
         #[arg(long, help = "Open browser automatically when server starts")]
         open: bool,
+
+        /// Authentication token for both Basic Auth (password) and Bearer token
+        #[arg(long, help = "Authentication token to secure the web interface")]
+        auth_token: Option<String>,
     },
 }
 
@@ -1211,8 +1215,13 @@ pub async fn cli() -> Result<()> {
             }
             return Ok(());
         }
-        Some(Command::Web { port, host, open }) => {
-            crate::commands::web::handle_web(port, host, open).await?;
+        Some(Command::Web {
+            port,
+            host,
+            open,
+            auth_token,
+        }) => {
+            crate::commands::web::handle_web(port, host, open, auth_token).await?;
             return Ok(());
         }
         None => {
diff --git a/crates/goose-cli/src/commands/web.rs b/crates/goose-cli/src/commands/web.rs
index 4543065d38b0..f9bb53c0f27a 100644
--- a/crates/goose-cli/src/commands/web.rs
+++ b/crates/goose-cli/src/commands/web.rs
@@ -1,26 +1,27 @@
 use anyhow::Result;
+use axum::response::Redirect;
 use axum::{
     extract::{
         ws::{Message, WebSocket, WebSocketUpgrade},
-        State,
+        Request, State,
     },
+    http::StatusCode,
+    middleware::{self, Next},
     response::{Html, IntoResponse, Response},
     routing::get,
     Json, Router,
 };
-use goose::session::SessionManager;
-use webbrowser;
-
+use base64::Engine;
 use futures::{sink::SinkExt, stream::StreamExt};
 use goose::agents::{Agent, AgentEvent};
 use goose::conversation::message::Message as GooseMessage;
-
-use axum::response::Redirect;
+use goose::session::SessionManager;
 use serde::{Deserialize, Serialize};
 use std::{net::SocketAddr, sync::Arc};
 use tokio::sync::{Mutex, RwLock};
 use tower_http::cors::{Any, CorsLayer};
 use tracing::error;
+use webbrowser;
 
 type CancellationStore = Arc<RwLock<std::collections::HashMap<String, tokio::task::AbortHandle>>>;
 
@@ -28,6 +29,7 @@ type CancellationStore = Arc<RwLock<std::collections::HashMap<String, tokio::tas
 struct AppState {
     agent: Arc<Agent>,
     cancellations: CancellationStore,
+    auth_token: Option<String>,
 }
 
 #[derive(Serialize, Deserialize)]
@@ -78,7 +80,59 @@ enum WebSocketMessage {
     Complete { message: String },
 }
 
-pub async fn handle_web(port: u16, host: String, open: bool) -> Result<()> {
+async fn auth_middleware(
+    State(state): State<AppState>,
+    req: Request,
+    next: Next,
+) -> Result<Response, StatusCode> {
+    // Skip auth for health check
+    if req.uri().path() == "/api/health" {
+        return Ok(next.run(req).await);
+    }
+
+    // If no auth token is configured, skip authentication entirely
+    let Some(ref expected_token) = state.auth_token else {
+        return Ok(next.run(req).await);
+    };
+
+    // Check for Bearer token first
+    if let Some(auth_header) = req.headers().get("authorization") {
+        if let Ok(auth_str) = auth_header.to_str() {
+            if let Some(token) = auth_str.strip_prefix("Bearer ") {
+                if token == expected_token {
+                    return Ok(next.run(req).await);
+                }
+            }
+
+            // Check for Basic auth (password-only, ignore username)
+            if let Some(basic_token) = auth_str.strip_prefix("Basic ") {
+                if let Ok(decoded) = base64::engine::general_purpose::STANDARD.decode(basic_token) {
+                    if let Ok(credentials) = String::from_utf8(decoded) {
+                        if credentials.ends_with(expected_token) {
+                            return Ok(next.run(req).await);
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    // Authentication failed - return 401 with WWW-Authenticate header
+    let mut response = Response::new("Authentication required".into());
+    *response.status_mut() = StatusCode::UNAUTHORIZED;
+    response.headers_mut().insert(
+        "WWW-Authenticate",
+        "Basic realm=\"Goose Web Interface\"".parse().unwrap(),
+    );
+    Ok(response)
+}
+
+pub async fn handle_web(
+    port: u16,
+    host: String,
+    open: bool,
+    auth_token: Option<String>,
+) -> Result<()> {
     // Setup logging
     crate::logging::setup_logging(Some("goose-web"), None)?;
 
@@ -125,6 +179,7 @@ pub async fn handle_web(port: u16, host: String, open: bool) -> Result<()> {
     let state = AppState {
         agent: Arc::new(agent),
         cancellations: Arc::new(RwLock::new(std::collections::HashMap::new())),
+        auth_token,
     };
 
     // Build router
@@ -136,6 +191,10 @@ pub async fn handle_web(port: u16, host: String, open: bool) -> Result<()> {
         .route("/api/sessions", get(list_sessions))
         .route("/api/sessions/{session_id}", get(get_session))
         .route("/static/{*path}", get(serve_static))
+        .layer(middleware::from_fn_with_state(
+            state.clone(),
+            auth_middleware,
+        ))
         .layer(
             CorsLayer::new()
                 .allow_origin(Any)