diff --git a/src/runtime/cgo/gcc_openbsd_386.c b/src/runtime/cgo/gcc_openbsd_386.c
index 22941a4c6d..1bc61ff708 100644
--- a/src/runtime/cgo/gcc_openbsd_386.c
+++ b/src/runtime/cgo/gcc_openbsd_386.c
@@ -13,9 +13,15 @@
 static void* threadentry(void*);
 static void (*setg_gcc)(void*);
 
-// TCB_SIZE is sizeof(struct thread_control_block),
-// as defined in /usr/src/lib/librthread/tcb.h
+// TCB_SIZE is sizeof(struct thread_control_block), as defined in
+// /usr/src/lib/librthread/tcb.h on OpenBSD 5.9 and earlier.
 #define TCB_SIZE (4 * sizeof(void *))
+
+// TIB_SIZE is sizeof(struct tib), as defined in
+// /usr/include/tib.h on OpenBSD 6.0 and later.
+#define TIB_SIZE (4 * sizeof(void *) + 6 * sizeof(int))
+
+// TLS_SIZE is the size of TLS needed for Go.
 #define TLS_SIZE (2 * sizeof(void *))
 
 void *__get_tcb(void);
@@ -29,25 +35,38 @@ struct thread_args {
 	void *arg;
 };
 
+static int has_tib = 0;
+
 static void
 tcb_fixup(int mainthread)
 {
-	void *newtcb, *oldtcb;
+	void *tls, *newtcb, *oldtcb;
+	size_t tls_size, tcb_size;
+
+	// TODO(jsing): Remove once OpenBSD 6.1 is released and OpenBSD 5.9 is
+	// no longer supported.
 
 	// The OpenBSD ld.so(1) does not currently support PT_TLS. As a result,
 	// we need to allocate our own TLS space while preserving the existing
-	// TCB that has been setup via librthread.
+	// TCB or TIB that has been setup via librthread.
 
-	newtcb = malloc(TCB_SIZE + TLS_SIZE);
-	if(newtcb == NULL)
+	tcb_size = has_tib ? TIB_SIZE : TCB_SIZE;
+	tls_size = TLS_SIZE + tcb_size;
+	tls = malloc(tls_size);
+	if(tls == NULL)
 		abort();
 
 	// The signal trampoline expects the TLS slots to be zeroed.
-	bzero(newtcb, TLS_SIZE);
+	bzero(tls, TLS_SIZE);
 
 	oldtcb = __get_tcb();
-	bcopy(oldtcb, newtcb + TLS_SIZE, TCB_SIZE);
-	__set_tcb(newtcb + TLS_SIZE);
+	newtcb = tls + TLS_SIZE;
+	bcopy(oldtcb, newtcb, tcb_size);
+	if(has_tib) {
+		 // Fix up self pointer.
+		*(uintptr_t *)(newtcb) = (uintptr_t)newtcb;
+	}
+	__set_tcb(newtcb);
 
 	// NOTE(jsing, minux): we can't free oldtcb without causing double-free
 	// problem. so newtcb will be memory leaks. Get rid of this when OpenBSD
@@ -79,6 +98,10 @@ static void init_pthread_wrapper(void) {
 		fprintf(stderr, "runtime/cgo: dlsym failed to find pthread_create: %s\n", dlerror());
 		abort();
 	}
+	// _rthread_init is hidden in OpenBSD librthread that has TIB.
+	if(dlsym(handle, "_rthread_init") == NULL) {
+		has_tib = 1;
+	}
 	dlclose(handle);
 }
 
@@ -144,6 +167,7 @@ _cgo_sys_thread_start(ThreadStart *ts)
 
 	pthread_attr_init(&attr);
 	pthread_attr_getstacksize(&attr, &size);
+
 	// Leave stacklo=0 and set stackhi=size; mstack will do the rest.
 	ts->g->stackhi = size;
 	err = sys_pthread_create(&p, &attr, threadentry, ts);
diff --git a/src/runtime/cgo/gcc_openbsd_amd64.c b/src/runtime/cgo/gcc_openbsd_amd64.c
index e84fe6c18b..4d4d14314c 100644
--- a/src/runtime/cgo/gcc_openbsd_amd64.c
+++ b/src/runtime/cgo/gcc_openbsd_amd64.c
@@ -13,9 +13,15 @@
 static void* threadentry(void*);
 static void (*setg_gcc)(void*);
 
-// TCB_SIZE is sizeof(struct thread_control_block),
-// as defined in /usr/src/lib/librthread/tcb.h
+// TCB_SIZE is sizeof(struct thread_control_block), as defined in
+// /usr/src/lib/librthread/tcb.h on OpenBSD 5.9 and earlier.
 #define TCB_SIZE (4 * sizeof(void *))
+
+// TIB_SIZE is sizeof(struct tib), as defined in
+// /usr/include/tib.h on OpenBSD 6.0 and later.
+#define TIB_SIZE (4 * sizeof(void *) + 6 * sizeof(int))
+
+// TLS_SIZE is the size of TLS needed for Go.
 #define TLS_SIZE (2 * sizeof(void *))
 
 void *__get_tcb(void);
@@ -29,25 +35,38 @@ struct thread_args {
 	void *arg;
 };
 
+static int has_tib = 0;
+
 static void
 tcb_fixup(int mainthread)
 {
-	void *newtcb, *oldtcb;
+	void *tls, *newtcb, *oldtcb;
+	size_t tls_size, tcb_size;
+
+	// TODO(jsing): Remove once OpenBSD 6.1 is released and OpenBSD 5.9 is
+	// no longer supported.
 
 	// The OpenBSD ld.so(1) does not currently support PT_TLS. As a result,
 	// we need to allocate our own TLS space while preserving the existing
-	// TCB that has been setup via librthread.
+	// TCB or TIB that has been setup via librthread.
 
-	newtcb = malloc(TCB_SIZE + TLS_SIZE);
-	if(newtcb == NULL)
+	tcb_size = has_tib ? TIB_SIZE : TCB_SIZE;
+	tls_size = TLS_SIZE + tcb_size;
+	tls = malloc(tls_size);
+	if(tls == NULL)
 		abort();
 
 	// The signal trampoline expects the TLS slots to be zeroed.
-	bzero(newtcb, TLS_SIZE);
+	bzero(tls, TLS_SIZE);
 
 	oldtcb = __get_tcb();
-	bcopy(oldtcb, newtcb + TLS_SIZE, TCB_SIZE);
-	__set_tcb(newtcb + TLS_SIZE);
+	newtcb = tls + TLS_SIZE;
+	bcopy(oldtcb, newtcb, tcb_size);
+	if(has_tib) {
+		 // Fix up self pointer.
+		*(uintptr_t *)(newtcb) = (uintptr_t)newtcb;
+	}
+	__set_tcb(newtcb);
 
 	// NOTE(jsing, minux): we can't free oldtcb without causing double-free
 	// problem. so newtcb will be memory leaks. Get rid of this when OpenBSD
@@ -79,6 +98,10 @@ static void init_pthread_wrapper(void) {
 		fprintf(stderr, "runtime/cgo: dlsym failed to find pthread_create: %s\n", dlerror());
 		abort();
 	}
+	// _rthread_init is hidden in OpenBSD librthread that has TIB.
+	if(dlsym(handle, "_rthread_init") == NULL) {
+		has_tib = 1;
+	}
 	dlclose(handle);
 }