diff --git a/mlir/lib/Analysis/AffineAnalysis.cpp b/mlir/lib/Analysis/AffineAnalysis.cpp
index c8022e046548..9f976a63c145 100644
--- a/mlir/lib/Analysis/AffineAnalysis.cpp
+++ b/mlir/lib/Analysis/AffineAnalysis.cpp
@@ -32,8 +32,6 @@
 
 using namespace mlir;
 
-using llvm::dbgs;
-
 /// Get the value that is being reduced by `pos`-th reduction in the loop if
 /// such a reduction can be performed by affine parallel loops. This assumes
 /// floating-point operations are commutative. On success, `kind` will be the
diff --git a/mlir/lib/Dialect/Linalg/Transforms/Fusion.cpp b/mlir/lib/Dialect/Linalg/Transforms/Fusion.cpp
index 90c9b0808f9b..0e0bc1ad48d1 100644
--- a/mlir/lib/Dialect/Linalg/Transforms/Fusion.cpp
+++ b/mlir/lib/Dialect/Linalg/Transforms/Fusion.cpp
@@ -38,8 +38,6 @@
 using namespace mlir;
 using namespace mlir::linalg;
 
-using llvm::dbgs;
-
 /// Implements a simple high-level fusion pass on linalg structured operations.
 ///
 /// In each block, linalg ops are processed in reverse textual order.
diff --git a/mlir/lib/Dialect/Linalg/Transforms/Vectorization.cpp b/mlir/lib/Dialect/Linalg/Transforms/Vectorization.cpp
index 17e78d085d06..939400ed5027 100644
--- a/mlir/lib/Dialect/Linalg/Transforms/Vectorization.cpp
+++ b/mlir/lib/Dialect/Linalg/Transforms/Vectorization.cpp
@@ -38,8 +38,6 @@
 using namespace mlir;
 using namespace mlir::linalg;
 
-using llvm::dbgs;
-
 #define DEBUG_TYPE "linalg-vectorization"
 
 #define DBGS() (llvm::dbgs() << '[' << DEBUG_TYPE << "] ")
diff --git a/mlir/lib/IR/MLIRContext.cpp b/mlir/lib/IR/MLIRContext.cpp
index 7e811316c4e6..f4ffc297de99 100644
--- a/mlir/lib/IR/MLIRContext.cpp
+++ b/mlir/lib/IR/MLIRContext.cpp
@@ -43,8 +43,6 @@
 using namespace mlir;
 using namespace mlir::detail;
 
-using llvm::hash_combine;
-
 //===----------------------------------------------------------------------===//
 // MLIRContext CommandLine Options
 //===----------------------------------------------------------------------===//
diff --git a/mlir/lib/Parser/AffineParser.cpp b/mlir/lib/Parser/AffineParser.cpp
index 1ba2ad5c7a2d..9bff88a7f167 100644
--- a/mlir/lib/Parser/AffineParser.cpp
+++ b/mlir/lib/Parser/AffineParser.cpp
@@ -17,9 +17,7 @@
 
 using namespace mlir;
 using namespace mlir::detail;
-using llvm::MemoryBuffer;
 using llvm::SMLoc;
-using llvm::SourceMgr;
 
 namespace {
 
diff --git a/mlir/lib/Parser/Lexer.cpp b/mlir/lib/Parser/Lexer.cpp
index 56ffc90cf6e8..5a882d08594f 100644
--- a/mlir/lib/Parser/Lexer.cpp
+++ b/mlir/lib/Parser/Lexer.cpp
@@ -20,7 +20,6 @@
 using namespace mlir;
 
 using llvm::SMLoc;
-using llvm::SourceMgr;
 
 // Returns true if 'c' is an allowable punctuation character: [$._-]
 // Returns false otherwise.
diff --git a/mlir/tools/mlir-linalg-ods-gen/mlir-linalg-ods-yaml-gen.cpp b/mlir/tools/mlir-linalg-ods-gen/mlir-linalg-ods-yaml-gen.cpp
index 7651e19b43c2..a07ada3c8e66 100644
--- a/mlir/tools/mlir-linalg-ods-gen/mlir-linalg-ods-yaml-gen.cpp
+++ b/mlir/tools/mlir-linalg-ods-gen/mlir-linalg-ods-yaml-gen.cpp
@@ -30,7 +30,6 @@
 using namespace mlir;
 
 using llvm::yaml::Input;
-using llvm::yaml::IO;
 using llvm::yaml::MappingTraits;
 using llvm::yaml::ScalarEnumerationTraits;
 using llvm::yaml::ScalarTraits;
diff --git a/mlir/tools/mlir-tblgen/DirectiveCommonGen.cpp b/mlir/tools/mlir-tblgen/DirectiveCommonGen.cpp
index aaad51794821..7cca598cc6ec 100644
--- a/mlir/tools/mlir-tblgen/DirectiveCommonGen.cpp
+++ b/mlir/tools/mlir-tblgen/DirectiveCommonGen.cpp
@@ -22,7 +22,6 @@ using llvm::Clause;
 using llvm::ClauseVal;
 using llvm::raw_ostream;
 using llvm::RecordKeeper;
-using llvm::Twine;
 
 // LLVM has multiple places (Clang, Flang, MLIR) where information about
 // the directives (OpenMP/OpenACC), and clauses are needed. It is good software
diff --git a/mlir/tools/mlir-tblgen/SPIRVUtilsGen.cpp b/mlir/tools/mlir-tblgen/SPIRVUtilsGen.cpp
index ad0b05e4c47b..683307229e13 100644
--- a/mlir/tools/mlir-tblgen/SPIRVUtilsGen.cpp
+++ b/mlir/tools/mlir-tblgen/SPIRVUtilsGen.cpp
@@ -40,7 +40,6 @@ using llvm::SmallVector;
 using llvm::SMLoc;
 using llvm::StringMap;
 using llvm::StringRef;
-using llvm::Twine;
 using mlir::tblgen::Attribute;
 using mlir::tblgen::EnumAttr;
 using mlir::tblgen::EnumAttrCase;