diff --git a/spec/main/unit/proxy.spec.ts b/spec/main/unit/proxy.spec.ts
new file mode 100644
index 00000000..16ad4c32
--- /dev/null
+++ b/spec/main/unit/proxy.spec.ts
@@ -0,0 +1,60 @@
+import path from 'path'
+import ProxyConfiguration from '~/src/main/proxy'
+import { ManualProxy, ProxyProtocol } from '~/src/types/proxy'
+
+const preferencesDBPath = path.resolve(__dirname, '../../preferences.json')
+const proxyConfiguration = new ProxyConfiguration(preferencesDBPath)
+
+describe('Parser', () => {
+  it('do not use proxy', () => {
+    proxyConfiguration.setSystemProxy('DIRECT')
+    const proxy = proxyConfiguration.parseSystemProxy()
+    expect(proxy).toEqual(false)
+  })
+
+  it('HTTP and HTTPS proxy', () => {
+    proxyConfiguration.setSystemProxy('PROXY hoge.example.com:8080')
+    const proxy = proxyConfiguration.parseSystemProxy()
+    expect(proxy).not.toBe(false)
+    const manualProxy = proxy as ManualProxy
+    expect(manualProxy.protocol).toEqual(ProxyProtocol.http)
+    expect(manualProxy.host).toEqual('hoge.example.com')
+    expect(manualProxy.port).toEqual('8080')
+  })
+
+  it('SOCKS4 proxy', () => {
+    proxyConfiguration.setSystemProxy('SOCKS4 hoge.example.com:8080')
+    const proxy = proxyConfiguration.parseSystemProxy()
+    expect(proxy).not.toBe(false)
+    const manualProxy = proxy as ManualProxy
+    expect(manualProxy.protocol).toEqual(ProxyProtocol.socks4)
+  })
+  it('SOCKS4A proxy', () => {
+    proxyConfiguration.setSystemProxy('SOCKS4A hoge.example.com:8080')
+    const proxy = proxyConfiguration.parseSystemProxy()
+    expect(proxy).not.toBe(false)
+    const manualProxy = proxy as ManualProxy
+    expect(manualProxy.protocol).toEqual(ProxyProtocol.socks4a)
+  })
+  it('SOCKS5 proxy', () => {
+    proxyConfiguration.setSystemProxy('SOCKS5 hoge.example.com:8080')
+    const proxy = proxyConfiguration.parseSystemProxy()
+    expect(proxy).not.toBe(false)
+    const manualProxy = proxy as ManualProxy
+    expect(manualProxy.protocol).toEqual(ProxyProtocol.socks5)
+  })
+  it('SOCKS5H proxy', () => {
+    proxyConfiguration.setSystemProxy('SOCKS5H hoge.example.com:8080')
+    const proxy = proxyConfiguration.parseSystemProxy()
+    expect(proxy).not.toBe(false)
+    const manualProxy = proxy as ManualProxy
+    expect(manualProxy.protocol).toEqual(ProxyProtocol.socks5h)
+  })
+  it('SOCKS proxy', () => {
+    proxyConfiguration.setSystemProxy('SOCKS hoge.example.com:8080')
+    const proxy = proxyConfiguration.parseSystemProxy()
+    expect(proxy).not.toBe(false)
+    const manualProxy = proxy as ManualProxy
+    expect(manualProxy.protocol).toEqual(ProxyProtocol.socks5)
+  })
+})
diff --git a/spec/preferences.json b/spec/preferences.json
new file mode 100644
index 00000000..0967ef42
--- /dev/null
+++ b/spec/preferences.json
@@ -0,0 +1 @@
+{}
diff --git a/src/main/index.ts b/src/main/index.ts
index 23d90e7b..646c574f 100644
--- a/src/main/index.ts
+++ b/src/main/index.ts
@@ -4,6 +4,7 @@ import {
   app,
   ipcMain,
   shell,
+  session,
   Menu,
   Tray,
   BrowserWindow,
@@ -45,6 +46,7 @@ import HashtagCache from './cache/hashtag'
 import AccountCache from './cache/account'
 import { InsertAccountCache } from '~/src/types/insertAccountCache'
 import { Proxy } from '~/src/types/proxy'
+import ProxyConfiguration from './proxy'
 
 /**
  * Context menu
@@ -144,6 +146,7 @@ const soundBasePath =
   process.env.NODE_ENV === 'development' ? path.join(__dirname, '../../build/sounds/') : path.join(process.resourcesPath!, 'build/sounds/')
 
 let launcher: AutoLaunch | null = null
+const proxyConfiguration = new ProxyConfiguration(preferencesDBPath)
 
 // On MAS build, auto launch is not working.
 // We have to use Launch Agent: https://github.com/Teamwork/node-auto-launch/issues/43
@@ -270,6 +273,16 @@ async function createWindow() {
 
   mainWindow.webContents.on('will-navigate', event => event.preventDefault())
 
+  /**
+   * Get system proxy configuration.
+   */
+  if (session && session.defaultSession) {
+    session.defaultSession.resolveProxy('https://mastodon.social', proxyInfo => {
+      proxyConfiguration.setSystemProxy(proxyInfo)
+      log.info(`System proxy configuration: ${proxyInfo}`)
+    })
+  }
+
   mainWindow.on('closed', () => {
     mainWindow = null
   })
@@ -982,6 +995,11 @@ ipcMain.on('update-proxy-config', (event: IpcMainEvent, proxy: Proxy) => {
     })
 })
 
+ipcMain.on('get-proxy-configuration', async (event: IpcMainEvent) => {
+  const proxy = await proxyConfiguration.getConfig()
+  event.sender.send('response-get-proxy-configuration', proxy)
+})
+
 // language
 ipcMain.on('change-language', (event: IpcMainEvent, value: string) => {
   const preferences = new Preferences(preferencesDBPath)
diff --git a/src/main/preferences.ts b/src/main/preferences.ts
index 2fb8a62d..1a74df1c 100644
--- a/src/main/preferences.ts
+++ b/src/main/preferences.ts
@@ -1,4 +1,5 @@
 import storage from 'electron-json-storage'
+import log from 'electron-log'
 import objectAssignDeep from 'object-assign-deep'
 import DisplayStyle from '../constants/displayStyle'
 import Theme from '../constants/theme'
@@ -97,6 +98,7 @@ export default class Preferences {
       const preferences = await this.get()
       return objectAssignDeep({}, Base, preferences)
     } catch (err) {
+      log.error(err)
       return Base
     }
   }
diff --git a/src/main/proxy.ts b/src/main/proxy.ts
new file mode 100644
index 00000000..2d5c4f7e
--- /dev/null
+++ b/src/main/proxy.ts
@@ -0,0 +1,74 @@
+import { ProxySource, ManualProxy, ProxyProtocol } from '~/src/types/proxy'
+import Preferences from './preferences'
+
+export default class ProxyConfiguration {
+  public preferences: Preferences
+  public systemProxy: string | null = null
+
+  constructor(preferencesDBPath: string) {
+    this.preferences = new Preferences(preferencesDBPath)
+  }
+
+  public setSystemProxy(proxy: string) {
+    this.systemProxy = proxy
+  }
+
+  public async getConfig(): Promise<false | ManualProxy> {
+    const conf = await this.preferences.get()
+    const source = conf.proxy.source as ProxySource
+    switch (source) {
+      case ProxySource.no:
+        return false
+      case ProxySource.system:
+        if (this.systemProxy) {
+          return this.parseSystemProxy()
+        } else {
+          return false
+        }
+      case ProxySource.manual:
+        return conf.proxy.manualProxyConfig
+    }
+  }
+
+  public parseSystemProxy(): ManualProxy | false {
+    if (!this.systemProxy) {
+      return false
+    }
+    if (this.systemProxy === 'DIRECT') {
+      return false
+    }
+    const result = this.systemProxy.match(/^([A-Z0-9]+)\s+([a-z0-9-_.]+):([0-9]+)$/)
+    if (!result || result.length !== 4) {
+      return false
+    }
+    let protocol = ProxyProtocol.http
+    switch (result[1]) {
+      case 'PROXY':
+        protocol = ProxyProtocol.http
+        break
+      case 'SOCKS4':
+        protocol = ProxyProtocol.socks4
+        break
+      case 'SOCKS4A':
+        protocol = ProxyProtocol.socks4a
+        break
+      case 'SOCKS5':
+        protocol = ProxyProtocol.socks5
+        break
+      case 'SOCKS5H':
+        protocol = ProxyProtocol.socks5h
+        break
+      case 'SOCKS':
+        protocol = ProxyProtocol.socks5
+        break
+    }
+    const manual: ManualProxy = {
+      protocol: protocol,
+      host: result[2],
+      port: result[3],
+      username: '',
+      password: ''
+    }
+    return manual
+  }
+}