Preheat grill to medium-high heat.
In a large bowl, toss salmon cubes with olive oil, salt, pepper, and half the chimichurri sauce.
Thread salmon pieces and lemon slices alternately onto skewers.
Grill skewers for 2-3 minutes per side, until salmon is just cooked through.
Remove from grill and drizzle with remaining chimichurri sauce before serving.