diff --git a/mlir/test/mlir-tblgen/op-decl.td b/mlir/test/mlir-tblgen/op-decl.td
--- a/mlir/test/mlir-tblgen/op-decl.td
+++ b/mlir/test/mlir-tblgen/op-decl.td
@@ -1,4 +1,5 @@
 // RUN: mlir-tblgen -gen-op-decls -I %S/../../include %s | FileCheck  %s
+// RUN: mlir-tblgen -gen-op-decls -op-regex="test.a_op" -I %S/../../include %s | FileCheck  %s --check-prefix=REDUCE
 
 include "mlir/IR/OpBase.td"
 include "mlir/Interfaces/InferTypeOpInterface.td"
@@ -195,3 +196,5 @@
 // CHECK-LABEL: _BOp declarations
 // CHECK: class _BOp : public Op<_BOp
 
+// REDUCE-LABEL: NS::AOp declarations
+// REDUCE-NOT: NS::BOp declarations
diff --git a/mlir/tools/mlir-tblgen/OpDefinitionsGen.cpp b/mlir/tools/mlir-tblgen/OpDefinitionsGen.cpp
--- a/mlir/tools/mlir-tblgen/OpDefinitionsGen.cpp
+++ b/mlir/tools/mlir-tblgen/OpDefinitionsGen.cpp
@@ -21,6 +21,8 @@
 #include "mlir/TableGen/SideEffects.h"
 #include "llvm/ADT/Sequence.h"
 #include "llvm/ADT/StringExtras.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Regex.h"
 #include "llvm/Support/Signals.h"
 #include "llvm/TableGen/Error.h"
 #include "llvm/TableGen/Record.h"
@@ -32,6 +34,13 @@
 using namespace mlir;
 using namespace mlir::tblgen;
 
+cl::OptionCategory opDefGenCat("Options for -gen-op-defs and -gen-op-decls");
+
+static cl::opt<std::string>
+    opFilter("op-regex",
+             cl::desc("Regex of name of op's to filter (no filter if empty)"),
+             cl::cat(opDefGenCat));
+
 static const char *const tblgenNamePrefix = "tblgen_";
 static const char *const generatedArgName = "odsArg";
 static const char *const builderOpState = "odsState";
@@ -2081,10 +2090,37 @@
       [&os]() { os << ",\n"; });
 }
 
+static std::string getOperationName(const Record &def) {
+  auto prefix = def.getValueAsDef("opDialect")->getValueAsString("name");
+  auto opName = def.getValueAsString("opName");
+  if (prefix.empty())
+    return std::string(opName);
+  return std::string(llvm::formatv("{0}.{1}", prefix, opName));
+}
+
+static std::vector<Record *>
+getAllDerivedDefinitions(const RecordKeeper &recordKeeper,
+                         StringRef className) {
+  Record *classDef = recordKeeper.getClass(className);
+  if (!classDef)
+    PrintFatalError("ERROR: Couldn't find the `" + className + "' class!\n");
+
+  llvm::Regex includeRegex(opFilter);
+  std::vector<Record *> defs;
+  for (const auto &def : recordKeeper.getDefs()) {
+    if (def.second->isSubClassOf(classDef)) {
+      if (opFilter.empty() || includeRegex.match(getOperationName(*def.second)))
+        defs.push_back(def.second.get());
+    }
+  }
+
+  return defs;
+}
+
 static bool emitOpDecls(const RecordKeeper &recordKeeper, raw_ostream &os) {
   emitSourceFileHeader("Op Declarations", os);
 
-  const auto &defs = recordKeeper.getAllDerivedDefinitions("Op");
+  const auto &defs = getAllDerivedDefinitions(recordKeeper, "Op");
   emitOpClasses(defs, os, /*emitDecl=*/true);
 
   return false;
@@ -2093,7 +2129,7 @@
 static bool emitOpDefs(const RecordKeeper &recordKeeper, raw_ostream &os) {
   emitSourceFileHeader("Op Definitions", os);
 
-  const auto &defs = recordKeeper.getAllDerivedDefinitions("Op");
+  const auto &defs = getAllDerivedDefinitions(recordKeeper, "Op");
   emitOpList(defs, os);
   emitOpClasses(defs, os, /*emitDecl=*/false);