Spearfishing Knives: What’s The Big Deal?

Of all the tools out there that a spearo requires a spearfishing knife is one that a lot of people raise an eyebrow at. Sometimes I find myself raising two eyebrows at the size of some general purpose diving knives that are available on the market.


Don’t get me wrong, they are awesome and I am just as obsessed with cool knives as anyone and more than that, huge knives do have their places in the diving world. How they relate to spearfishing is an entirely different animal however.
Spearfishing knives are very useful and serve two very specific purposes.

1.) To humanely end the life of your speared fish


As spearos, we have a responsibility to the animals that we take to treat them with respect. Weather you feel this is true or not, there are thousands upon thousands of people out there with a close eye on us and how we treat our ocean environment.


Quickly killing is simply good practice and if your shot does not do the job you may have to bust out your blade. So how do you properly kill a fish with a knife?


The guys at Reefari Reef Fishing & Charters show that the proper way is to sever the brain of the fish by inserting a knife between the eyes on top of the head and strongly rocking the knife back and forth.


Underwater this can translate to a couple well placed stabs if your fish is really large and still has the safe effect as long as the brain is affected.


2.) As a safety measure against entanglement.
Entanglement is one of those issues that never comes up until it comes up. Underwater this could be a huge issue and it’s important to be prepared.
Really anything that cuts will do the trick to release you from lines, but more importantly the bulk of the knife is what you’re trying to avoid. It’s crazy how easily knives can get stuck on things like mono filament, line and even organics like kelp and seagrass. That’s just plain obnoxious.
What Makes A Knife Great For Spearfishing?

Lots of little factors go into a great knife for spearfishing but if I were to use only one word it would be simplicity.


A knife should be so simple that it borders on boring and there are a lot of good reasons why. Let’s use some images to illustrate things a little bit better.



A knife should be really pointed for spearfishing. After all, the whole idea is to get it directly into the brain of the fish. Sounds a little gruesome I know, but with a semi-rounded knife this could become a troublesome task.



Nothing is more annoying than getting your float line or other manner of ocean FOD between your dive knife and your leg. It literally makes me mad and throws off my good mentality for a few minutes. Avoid this by grabbing a thin knife and sheath.



Serrated knives require a lot less effort to get through to where they need to go and offer the option to easily cut bone and tough stuff that burlier fish will throw at you. A simple rocking back and forth is all that is needed.





The sheath can be a little tough to get right since you have to see it with your own eyes. It’s recommended to get your hands on a sheath and knife before you buy if it you don’t have some in depth reviews to show you what’s up. How Much Should I Spend?

It’s kind of crazy how the small market of spearfishing knives only makes knives that are effective and affordable. If you end up spending over $60 on your knife you might have spent too much and with such a high mortality rate for dive knives it just doesn’t make sense to pay top dollar unless you want to. If you do, that’s cool too.
Here is a great knife to keep on you when you go spearfishing. It’s light, slim and really sharp. Simple is better! The Stubby from Riffe This knife is great because: It has a slim, yet full grip The sheath is simple The blade is serrated The whole thing lays pretty flat.



With that said, lets check out some popular dive knives and some reasons why they are useful for spearfishing. I’m going to keep them all under the $60 mark just to keep things simple and affordable.
Some Popular Spearfishing Knives

These knives are used pretty heavily by spearos and are easily 3 of the top performing spearfishing knives on the market. Don’t limit yourself to just these, but they represent the three main shapes and configurations that are out there.





This knife is reminiscent of an old military dive knife with its properly sized handle and intentional blade shape. There a lot of little serrations that make this blade tough as well as handy.





Most people absolutely love this knife on account of its small size and affordable price tag. Besides all of that, the knife performs like a dream with its razor-sharp tip and perfect size.





The Standard is the big brother to the Riffe Stubby which is mentioned above. It’s got great blade length and a still maintains the low profile, a great option if you need something longer.



How To Take Care Of Your Knife

Diving knives are pretty unique in that they are subjected to saltwater, quite possibly the most destructive element for metals.


Saltwater contains more oxygen and is more conducive to the oxidation of iron, which is found in most alloys.


Long story short, saltwater is pretty rough on knives and even with the reduction of materials that rust in dive knives, any knife that is made of some sort of steel still has the potential to rust. This makes caring for your stainless steel knife a pretty high priority.
Some Guidelines to follow for a happy knife.

1.) Rinse your knife with fresh water after every dive, never leave it overnight with saltwater on the blade.


2.) Apply a super thin coat of petroleum jelly to the blade once it had dried. This is a temporary fix but will safe you a little headache with a finicky knife.


3.) If your knife has a bit of surface rust, soak it in white vinegar for about an hour then gently rub the rust off with steel wool. (At your own risk, but it’s never hurt me.)
Thanks For Reading! I’m curious which knives you all have had experiences with. Since this is by no means a list of all the knives used for spearfishing I’d love to keep the conversation going in the comment section! Sign Me Up For Updates! If You Would Like To Be Notified When New Posts Are Published, Please Sign Up For Our Mailing List By Clicking The Button Above!


Spearfishing Knives is a post from: The Spearfishing Academy