diff --git a/CHANGELOG.md b/CHANGELOG.md
index fa2dead9474..2a256b96d1d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -30,6 +30,7 @@
 - Add metric_bucket data category. ([#2824](https://github.com/getsentry/relay/pull/2824))
 - Org rate limit metrics per bucket. ([#2836](https://github.com/getsentry/relay/pull/2836))
 - Keep only domain and extension for image resource span grouping. ([#2826](https://github.com/getsentry/relay/pull/2826))
+- Parse timestamps from strings in span OpenTelemetry schema. ([#2857](https://github.com/getsentry/relay/pull/2857))
 
 ## 23.11.2
 
diff --git a/relay-spans/src/lib.rs b/relay-spans/src/lib.rs
index 7e640f434ff..d8c489fe024 100644
--- a/relay-spans/src/lib.rs
+++ b/relay-spans/src/lib.rs
@@ -13,3 +13,4 @@ mod otel_to_sentry_tags;
 mod span;
 mod status_codes;
 mod trace;
+mod utils;
diff --git a/relay-spans/src/span.rs b/relay-spans/src/span.rs
index c64b2b6a207..c2c4c1f9607 100644
--- a/relay-spans/src/span.rs
+++ b/relay-spans/src/span.rs
@@ -4,6 +4,7 @@ use chrono::{TimeZone, Utc};
 use serde::{Deserialize, Serialize};
 use serde_repr::{Deserialize_repr, Serialize_repr};
 
+use crate::utils::deserialize_number_from_string;
 use relay_event_schema::protocol::{Span as EventSpan, SpanId, SpanStatus, Timestamp, TraceId};
 use relay_protocol::{Annotated, Object, Value};
 
@@ -69,6 +70,7 @@ pub struct OtelSpan {
     /// Value is UNIX Epoch time in nanoseconds since 00:00:00 UTC on 1 January 1970.
     ///
     /// This field is semantically required and it is expected that end_time >= start_time.
+    #[serde(deserialize_with = "deserialize_number_from_string")]
     pub start_time_unix_nano: i64,
     /// end_time_unix_nano is the end time of the span. On the client side, this is the time
     /// kept by the local machine where the span execution ends. On the server side, this
@@ -76,6 +78,7 @@ pub struct OtelSpan {
     /// Value is UNIX Epoch time in nanoseconds since 00:00:00 UTC on 1 January 1970.
     ///
     /// This field is semantically required and it is expected that end_time >= start_time.
+    #[serde(deserialize_with = "deserialize_number_from_string")]
     pub end_time_unix_nano: i64,
     /// attributes is a collection of key/value pairs. Note, global attributes
     /// like server name can be set using the resource API.
@@ -250,7 +253,7 @@ pub struct Event {
     /// This field is semantically required to be set to non-empty string.
     pub name: String,
     /// time_unix_nano is the time the event occurred.
-    #[serde(default)]
+    #[serde(default, deserialize_with = "deserialize_number_from_string")]
     pub time_unix_nano: u64,
 }
 
@@ -409,6 +412,7 @@ pub struct KeyValue {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use chrono::{DateTime, Utc};
     use relay_protocol::{get_path, Annotated};
 
     #[test]
@@ -523,4 +527,25 @@ mod tests {
         let event_span: EventSpan = otel_span.into();
         assert_eq!(event_span.exclusive_time, Annotated::new(0.0788));
     }
+
+    #[test]
+    fn parse_span_with_timestamps_as_strings() {
+        let json = r#"{
+            "traceId": "89143b0763095bd9c9955e8175d1fb23",
+            "spanId": "e342abb1214ca181",
+            "parentSpanId": "0c7a7dea069bf5a6",
+            "name": "middleware - fastify -> @fastify/multipart",
+            "kind": 1,
+            "startTimeUnixNano": "1697620454980000000",
+            "endTimeUnixNano": "1697620454980078800"
+        }"#;
+        let otel_span: OtelSpan = serde_json::from_str(json).unwrap();
+        let event_span: EventSpan = otel_span.into();
+        assert_eq!(
+            event_span.start_timestamp,
+            Annotated::new(Timestamp(
+                DateTime::<Utc>::from_timestamp(1697620454, 980000000).unwrap()
+            ))
+        );
+    }
 }
diff --git a/relay-spans/src/utils.rs b/relay-spans/src/utils.rs
new file mode 100644
index 00000000000..35ccde14066
--- /dev/null
+++ b/relay-spans/src/utils.rs
@@ -0,0 +1,41 @@
+use std::fmt::Display;
+use std::str::FromStr;
+
+use serde::{de, Deserialize};
+use serde_json::{Map, Value};
+
+pub fn deserialize_number_from_string<'de, T, D>(deserializer: D) -> Result<T, D::Error>
+where
+    D: de::Deserializer<'de>,
+    T: FromStr + Deserialize<'de>,
+    <T as FromStr>::Err: Display,
+{
+    #[derive(Deserialize)]
+    #[serde(untagged)]
+    enum AnyType<T> {
+        Array(Vec<Value>),
+        Bool(bool),
+        Null,
+        Number(T),
+        Object(Map<String, Value>),
+        String(String),
+    }
+
+    match AnyType::<T>::deserialize(deserializer)? {
+        AnyType::String(s) => s.parse::<T>().map_err(serde::de::Error::custom),
+        AnyType::Number(n) => Ok(n),
+        AnyType::Bool(v) => Err(serde::de::Error::custom(format!(
+            "unsupported value: {:?}",
+            v
+        ))),
+        AnyType::Array(v) => Err(serde::de::Error::custom(format!(
+            "unsupported value: {:?}",
+            v
+        ))),
+        AnyType::Object(v) => Err(serde::de::Error::custom(format!(
+            "unsupported value: {:?}",
+            v
+        ))),
+        AnyType::Null => Err(serde::de::Error::custom("unsupported null value")),
+    }
+}