Disarm action:
A creature can use a weapon attack to knock a weapon or another item from a target's grasp. The attacker makes an attack roll contested by the target's Strength (Athletics) check or Dexterity (Acrobatics) check. If the attacker wins the contest, the attack causes no damage or other ill effect, but the defender drops the item.


So can you do a disarm action as part of the attacks you get from flurry of blows? It seems in line with the description. What do you think? Do you use this with your monk?

I haven’t tried disarm but it should work as you describe. 

I would let a monk do that in my campaign that I DM. 

Flurry of Blows specifies that you make two Unarmed Strikes, which you're not doing if you trade one of them for a disarm (or grapple or shove). In other words, it's not giving you two bonus attacks that you can use however you like.

The obvious question though is; why would you need to? Are you thinking of cases where you've failed with your regular attack(s) and want to force more attempts (i.e- trying to brute force the enemy into losing its weapon in a single turn)?

Disarm is an action, not an option for your individual attacks. It uses up your action, you get one attempt, and because it's a distinct action from the Attack action you can't follow it up with a Flurry of Blows.

An option that does what you want is to take the Martial Adept feat and learn Disarming Attack. That would let you attempt to disarm the target with any weapon attack once per short rest.

Quote from InquisitiveCoder >>

Disarm is an action, not an option for your individual attacks. It uses up your action, you get one attempt, and because it's a distinct action from the Attack action you can't follow it up with a Flurry of Blows.

An option that does what you want is to take the Martial Adept feat and learn Disarming Attack. That would let you attempt to disarm the target with any weapon attack once per short rest.

 Your link didn’t work but I found the rule in the DMG. And you are correct, it is another type of action. I’m not familiar with all the DMG rules (I’m not a DM) and didn’t realize this. So you are right it doesn’t work with FoB  

From the OP’s quote I had assumed it was kind of like a grapple which, if you have extra attack, replaces only one attack so if that was the case it would work. 

Thanks

Quote from ThriKreenWarrior >>

Quote from InquisitiveCoder >>

Disarm is an action, not an option for your individual attacks. It uses up your action, you get one attempt, and because it's a distinct action from the Attack action you can't follow it up with a Flurry of Blows.

An option that does what you want is to take the Martial Adept feat and learn Disarming Attack. That would let you attempt to disarm the target with any weapon attack once per short rest.

 Your link didn’t work but I found the rule in the DMG. And you are correct, it is another type of action. I’m not familiar with all the DMG rules (I’m not a DM) and didn’t realize this. So you are right it doesn’t work with FoB  

From the OP’s quote I had assumed it was kind of like a grapple which, if you have extra attack, replaces only one attack so if that was the case it would work.

Whoops, looks like I made that assumption as well, though my post still applies to the others; you can't swap Flurry of Blows attacks for grapple or shove. Both can only be done as part of the Attack action; Flurry of Blows is a Bonus Action, and if even it weren't, it specifically lets you make unarmed strikes, it's not the same as Extra Attack. This applies to the Martial Arts bonus attack as well.

Oops! Here's the tweets I was trying to link to:

@JeremyECrawford does the Disarm option in DMG chapter 9 take up your action, or is it something you choose to do when making a weapon attack by any means?

It takes up your action.

Quote from Haravikk >>

Quote from ThriKreenWarrior >>

Quote from InquisitiveCoder >>

Disarm is an action, not an option for your individual attacks. It uses up your action, you get one attempt, and because it's a distinct action from the Attack action you can't follow it up with a Flurry of Blows.

An option that does what you want is to take the Martial Adept feat and learn Disarming Attack. That would let you attempt to disarm the target with any weapon attack once per short rest.

 Your link didn’t work but I found the rule in the DMG. And you are correct, it is another type of action. I’m not familiar with all the DMG rules (I’m not a DM) and didn’t realize this. So you are right it doesn’t work with FoB  

From the OP’s quote I had assumed it was kind of like a grapple which, if you have extra attack, replaces only one attack so if that was the case it would work.

Whoops, looks like I made that assumption as well, though my post still applies to the others; you can't swap Flurry of Blows attacks for grapple or shove. Both can only be done as part of the Attack action; Flurry of Blows is a Bonus Action, and if even it weren't, it specifically lets you make unarmed strikes, it's not the same as Extra Attack. This applies to the Martial Arts bonus attack as well.

 Yes, you should be able to grapple or shove as part of your attack action and then FoB (only requires you take the attack action which you are to grapple). Or, if you’re 5th level or higher, you can grapple with your first attack and if successful use an unarmed strike or monk weapon (only one handed so no versatile since your other hand is grappling) with your second attack and then use your Bonus Action to unarmed attack (BA martial arts attack requires an attack unarmed or monk weapon before it) or you can FoB. 

I think I have that correct.