diff --git a/gtsam_unstable/slam/tests/testPartialPriorFactor.cpp b/gtsam_unstable/slam/tests/testPartialPriorFactor.cpp
new file mode 100644
index 000000000..6cc70ef46
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+++ b/gtsam_unstable/slam/tests/testPartialPriorFactor.cpp
@@ -0,0 +1,114 @@
+/* ----------------------------------------------------------------------------
+
+ * GTSAM Copyright 2010, Georgia Tech Research Corporation,
+ * Atlanta, Georgia 30332-0415
+ * All Rights Reserved
+ * Authors: Frank Dellaert, et al. (see THANKS for the full author list)
+
+ * See LICENSE for the license information
+
+ * -------------------------------------------------------------------------- */
+
+#include <gtsam_unstable/slam/PartialPriorFactor.h>
+#include <gtsam/inference/Symbol.h>
+#include <gtsam/geometry/Pose3.h>
+#include <gtsam/base/numericalDerivative.h>
+#include <gtsam/base/TestableAssertions.h>
+#include <CppUnitLite/TestHarness.h>
+
+using namespace std;
+using namespace gtsam;
+
+
+// Pose representation is [ Rx Ry Rz Tx Ty Tz ].
+static const int kIndexRx = 0;
+static const int kIndexRy = 1;
+static const int kIndexRz = 2;
+static const int kIndexTx = 3;
+static const int kIndexTy = 4;
+static const int kIndexTz = 5;
+
+
+typedef PartialPriorFactor<Pose3> TestPartialPriorFactor;
+
+/// traits
+namespace gtsam {
+template<>
+struct traits<TestPartialPriorFactor> : public Testable<TestPartialPriorFactor> {
+};
+}
+
+/* ************************************************************************* */
+TEST(PartialPriorFactor, JacobianPartialTranslation) {
+  Key poseKey(1);
+  Pose3 measurement(Rot3::RzRyRx(0.15, -0.30, 0.45), Point3(-5.0, 8.0, -11.0));
+  SharedNoiseModel model = noiseModel::Isotropic::Sigma(1, 0.25);
+
+  TestPartialPriorFactor factor(poseKey, kIndexTy, measurement.translation().x(), model);
+
+  // Create a linearization point at the zero-error point
+  Pose3 pose(Rot3::RzRyRx(0.15, -0.30, 0.45), Point3(-5.0, 8.0, -11.0));
+
+  // Calculate numerical derivatives.
+  Matrix expectedH1 = numericalDerivative11<Vector, Pose3>(
+      boost::bind(&TestPartialPriorFactor::evaluateError, &factor, _1, boost::none), pose);
+
+  // Use the factor to calculate the derivative.
+  Matrix actualH1;
+  factor.evaluateError(pose, actualH1);
+
+  // Verify we get the expected error.
+  CHECK(assert_equal(expectedH1, actualH1, 1e-5));
+}
+
+/* ************************************************************************* */
+TEST(PartialPriorFactor, JacobianFullTranslation) {
+  Key poseKey(1);
+  Pose3 measurement(Rot3::RzRyRx(0.15, -0.30, 0.45), Point3(-5.0, 8.0, -11.0));
+  SharedNoiseModel model = noiseModel::Isotropic::Sigma(3, 0.25);
+
+  std::vector<size_t> translationIndices = { kIndexTx, kIndexTy, kIndexTz };
+  TestPartialPriorFactor factor(poseKey, translationIndices, measurement.translation(), model);
+
+  // Create a linearization point at the zero-error point
+  Pose3 pose(Rot3::RzRyRx(0.15, -0.30, 0.45), Point3(-5.0, 8.0, -11.0));
+
+  // Calculate numerical derivatives.
+  Matrix expectedH1 = numericalDerivative11<Vector, Pose3>(
+      boost::bind(&TestPartialPriorFactor::evaluateError, &factor, _1, boost::none), pose);
+
+  // Use the factor to calculate the derivative.
+  Matrix actualH1;
+  factor.evaluateError(pose, actualH1);
+
+  // Verify we get the expected error.
+  CHECK(assert_equal(expectedH1, actualH1, 1e-5));
+}
+
+/* ************************************************************************* */
+TEST(PartialPriorFactor, JacobianFullRotation) {
+  Key poseKey(1);
+  Pose3 measurement(Rot3::RzRyRx(0.15, -0.30, 0.45), Point3(-5.0, 8.0, -11.0));
+  SharedNoiseModel model = noiseModel::Isotropic::Sigma(3, 0.25);
+
+  std::vector<size_t> rotationIndices = { kIndexRx, kIndexRy, kIndexRz };
+  TestPartialPriorFactor factor(poseKey, rotationIndices, Rot3::Logmap(measurement.rotation()), model);
+
+  // Create a linearization point at the zero-error point
+  Pose3 pose(Rot3::RzRyRx(0.15, -0.30, 0.45), Point3(-5.0, 8.0, -11.0));
+
+  // Calculate numerical derivatives.
+  Matrix expectedH1 = numericalDerivative11<Vector, Pose3>(
+      boost::bind(&TestPartialPriorFactor::evaluateError, &factor, _1, boost::none), pose);
+
+  // Use the factor to calculate the derivative.
+  Matrix actualH1;
+  factor.evaluateError(pose, actualH1);
+
+  // Verify we get the expected error.
+  CHECK(assert_equal(expectedH1, actualH1, 1e-5));
+}
+
+/* ************************************************************************* */
+int main() { TestResult tr; return TestRegistry::runAllTests(tr); }
+/* ************************************************************************* */