Spicy Korean Cucumber Salad (Oi Muchim)

Korean Cucumber Salad (Oi Muchim) is a spicy, crunchy, and refreshing Korean side dish. This quick 15-minute salad combines crisp cucumbers with gochugaru, gochujang, and a savory-sweet dressing for bold, balanced flavors. Perfect with Korean BBQ, grilled meats, or rice dishes.

I love making Oi Muchim (오이무침), a crunchy, flavorful Korean cucumber salad that’s perfect when I have extra cucumbers at home. It’s a quick and easy side dish that everyone always welcomes.

This refreshing cucumber salad comes together in just minutes and is loaded with savory, tangy, slightly sweet, and gently spicy flavors from Korean chili flakes (gochugaru) and chili paste (gochujang).

But here’s the thing! if you mix it like a regular salad, the cucumbers can get watery fast and lose all that amazing flavor.

After lots of experimenting, I found a simple trick to keep it crisp and delicious for hours. If you’ve ever had soggy cucumber salad, you’ll love this easy, authentic Korean recipe!

Here’s What You’ll Need for Koran Cucumber Salad

Note on key ingredients:

• Cucumbers: Use a thin-skinned variety with a mild, slightly sweet taste. One medium English cucumber works well here. Kirby or Lebanese cucumbers are also great—use 2 to 3 since they’re smaller. If you’re using a waxy American cucumber, I recommend to peel off the thick skin.
• Gochugaru (Korean Chili Flakes): This is what gives Korean cucumber salad its signature red color and gentle heat. Gochugaru varies in spice level, so start small and adjust to taste. Avoid subbing with regular chili flakes—gochugaru is key to the authentic Korean flavor.
• Gochujang: A small spoonful of gochujang thickens the dressing and helps it coat the cucumbers better. It’s how my mom and grandma always made it—and to me, nothing beats this version. It adds rich depth without overwhelming the freshness.
• Gukganjang (Korean soup soy sauce): For bold umami flavor, add a splash of Korean soup soy sauce (gukganjang). Without it, the salad can taste flat—just spicy cucumbers. Gukganjang gives that deep, savory note that makes oi muchim truly Korean.

Making Korean Cucumber Salad (Step-by-Step)

These photos are here to give you a handy visual guide. For exact measurements and detailed steps, head to the full recipe card at the bottom of the post.

1. Salt the cucumbers and drain:
Sprinkle thin cucumber slices with a little salt and let them sit for 10 minutes. Rinse the cucumbers and gently squeeze out extra moisture. Even after salting, they’ll release a little water, but that’s okay! This trick is key to avoiding soggy, diluted salad—no more watery cucumber dishes

2. Add the dressing & toss:
Add thinly sliced onion with the rest of seasoning ingredients. Using your hands, lightly toss and massage the salad (the Korean “muchim” technique) until the cucumbers are well coated.

Did you know? The “muchim” method is a traditional Korean way to gently mix and help flavors soak in, giving the salad that perfect crunch! You’ll see the same technique in my Korean Spinach Namul recipe!

This spicy cucumber salad is the perfect banchan (side dish) for Korean BBQ (samgyupsal), or grilled fish like mackerel. The crisp, zesty bite balances out richer flavors beautifully!