No. While both are responsible for network security, the approach they adopt is different. Antivirus defends against security threats through surveillance. That is, by constantly looking out for malicious software (and not just viruses). Whereas firewall defends against security threats through governance. That is, by setting rules and forcing you and the internet to play by those rules.
1. Antivirus protects PC(s), Firewalls protect Networks: Your PC, the moment it goes online, comes into contact with several other PC(s). This means chances of your PC getting infected by malicious software are pretty high. And antivirus protects your PC(s) against such malware by constantly scanning your systems for such malware and terminating them.
Whereas firewalls are designed to protect your networks (your LAN(s) to be more precise) from incoming traffic by regulating them via various security-oriented policies. Simply put, they act as security guards between the internet and your LAN. Everything that passes into and out of your LAN should go through the firewall.
2. Antivirus Scan and Detect, Firewalls Filter or Sieve: Antivirus solutions scan, detect and eliminate viruses from your PC(s). Whereas firewalls minimize or regulate malware from entering into your network by filtering or sieving traffic which flows into your network. That is, they don’t offer security by taking action, they offer security through governance.
3. Antivirus Are Usually Installed, Firewall Security Comes Built-In: Users should separately install antivirus packages into their systems. With the only exception being the recent Windows 10’s Windows Defender antivirus, which security experts are suggesting is not enough to offer good security. Therefore, at the moment, PC users have to install antivirus packages to safeguard themselves against various security threats.
Whereas firewalls these days are built into PC(s), which can be turned ON or OFF by accessing the settings feature. But this is only with respect to a single PC. If you wish to secure your entire network, you need to purchase a firewall appliance, which is basically a router with built-in firewall features.
4. Antivirus Can Be Shared by Many PC(s), While Single PC Can Function As Firewall: Antivirus packages often offer discounts using which a single antivirus package can be shared by a network of computers. This way a single antivirus package will offer security for a number of PC(s) within the network.
Whereas a single server computer can be made to function as a firewall which protects the entire network.
5. Disadvantages – Antivirus Cause False Positives, Firewalls Affect Performance: As with everything, both have their disadvantages. With antivirus, it is false positives. That is, antivirus packages often make wrong guesses and may quarantine stuff which in reality will be harmless and can be useful to you.
With firewalls, network performance will be affected greatly. This happens because these tools inspect all incoming and outgoing traffic. Moreover, they are costly as well.