Let
G
be a simple, connected, and finite graph. For every vertex
v
∈
V
G
, we denote by
N
G
v
the set of neighbours of
v
in
G
. The locating-dominating number of a graph
G
is defined as the minimum cardinality of
W
⊆
V
G
such that every two distinct vertices
u
,
v
∈
V
G
\
W
satisfies
∅
≠
N
G
u
∩
W
≠
N
G
v
∩
W
≠
∅
. A graph
G
is called
k
-regular graph if every vertex of
G
is adjacent to
k
other vertices of
G
. In this paper, we determine the locating-dominating number of
k
-regular graph of order
n
, where
k
=
n
−
2
or
k
=
n
−
3
.